- Make the range-et-al optimizer produce E(#table records after table 
                                           condition is applied),
- Make the join optimizer use this value,
- Add "filtered" column to EXPLAIN EXTENDED to show 
  fraction of records left after table condition is applied
- Adjust test results, add comments


mysql-test/r/archive_gis.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/auto_increment.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/bdb_gis.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/bench_count_distinct.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/binlog_stm_blackhole.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/case.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/cast.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/compress.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/ctype_collate.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/ctype_cp1250_ch.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/date_formats.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/distinct.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/fulltext.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_compress.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_crypt.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_default.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_encrypt.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_gconcat.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_group.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_if.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_in.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_like.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_math.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_op.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_regexp.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_set.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_str.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_system.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_test.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/func_time.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/gis.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/group_by.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/group_min_max.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/having.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/heap.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/heap_hash.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/index_merge.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/index_merge_innodb.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/index_merge_ror.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/innodb_gis.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/insert_update.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/join.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/join_nested.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/key_diff.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/myisam.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/ndb_gis.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/negation_elimination.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/null.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/olap.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/partition_pruning.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/query_cache.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/row.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/rpl_get_lock.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/rpl_master_pos_wait.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/select.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/ssl.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/ssl_compress.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/subselect.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/type_blob.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/union.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/varbinary.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/variables.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/r/view.result:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/t/ctype_cp1250_ch.test:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/t/func_like.test:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/t/group_min_max.test:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/t/index_merge_ror.test:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/t/index_merge_ror_cpk.test:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/t/join.test:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
mysql-test/t/partition_pruning.test:
  BUG#14940: Adjust the test results: EXPLAIN EXTENDED now has extra "filtered" column
sql/opt_range.cc:
  BUG#14940: Make range/index_merge/group-min-max optimizer produce TABLE::quick_condition_rows -
    estimate of #records that will match the table condition.
sql/sql_class.cc:
  BUG#14940: Add "filtered" column to output of EXPLAIN EXTENDED
sql/sql_select.cc:
  BUG#14940: 
  - Make the join optimizer to use TABLE::quick_condition_rows=
    = E(#table records after filtering with table condition) 
  - Add "filtered" column to output of EXPLAIN EXTENDED
sql/sql_select.h:
  BUG#14940: Added comments
sql/table.h:
  BUG#14940: Added comments