that merges ON and WHERE (BUG#10162)

correct top_level_item for XOR

  Correction after manual merge.

  Added a test case for bug #9017.
item_cmpfunc.h:
  A wrong not_null_tables method for Item_cond_xor
  caused a conversion of a left join into an inner join
  that was not valid.

Item_func_equal::not_null_tables() always return 0.

updated with the correct number of lines. (Bug #8681)

so we read dependent tables after tables they depend on (this is needed for outer joins)

  Added cases for bugs #6307 and #6460.
sql_select.cc:
  Fixed the problem of bug reports #6307 and #6460.
  The reported wrong result sets were due to the fact that
  the added call of the fix_fields method for the built
  AND condition that joined WHERE and ON conditions
  broke ON expression, as it removed extra AND levels
  in the built condition. 
  It looks like that no attributes of the built condition
  are needed, so we don't have to call fix_fields here.

Added protocol::flush() for easier embedded-server code
Increase block allocation variables a bit as they where a bit too small for MySQL 4.1
Added option --silent to client_test

  Added a test case for bug #5896.
sql_select.cc:
  Fixed the problem of ignoring on expressions depending
  only on outer table when outer table either contains
  1 row or is guaranteed to return only 1 row (bug #5896).

 * When executing EXPLAIN, do the same as for the query: convert join type to JT_CONST if keyuse array covers all key parts and all of them are constants.
 * In remove_const, don't remove conditions that depend on some-const-table and current-table.

it happens because of the LEFT JOINT optimization in add_key_part()
This optimization does exactly the same in JOIN and in WHERE conditions 
Not right.
I moved that optimization one level upper.

Deprecate the use of TYPE=... Preferred syntax is ENGINE=

Added initialization of all important global variables

Added optimzation for clustered index
Fixed bug in UPDATE ... ORDER BY
Fixed handling of UPDATE ... LIMIT

e.g. default value is not accepted with auto_increment anymore.

Cleaned up test; Removed wrong DROP TABLE commands and use standard table and database names.
changed store_warning() -> push_warning_print()

Added missing InnoDB variables to SHOW VARIABLES.
Fixed bug when doing WHERE 'column_name=NULL' on an indexed column that had NULL values.
Fixed bug when doing 'LEFT JOIN ...  ON (column_name = constant) WHERE column_name = constant'

Fixed bug in LEFT JOIN
Added bdb_log_buffer_size

A lot of new tests to mysqltest
Fixed bug with BDB tables and autocommit