Fixed problem with UPDATE TABLE when keys wheren't always used.


Docs/manual.texi:
  Added comment to ALTER TABLE
scripts/mysql_install_db.sh:
  Added test for mysqld in libexec
sql/ha_innobase.cc:
  Removed compiler warning
sql/mysql_priv.h:
  Split setup_fields to setup_tables and setup_fields
sql/sql_base.cc:
  Split setup_fields to setup_tables and setup_fields
sql/sql_insert.cc:
  Split setup_fields to setup_tables and setup_fields
sql/sql_load.cc:
  Split setup_fields to setup_tables and setup_fields
sql/sql_parse.cc:
  Fixed missing 'mysql_info" with now clients.
sql/sql_select.cc:
  Split setup_fields to setup_tables and setup_fields
sql/sql_update.cc:
  Fixed problem with UPDATE TABLE when keys wheren't always used.
sql/sql_yacc.yy:
  Small isolation change