Docs/manual.texi:
  Changelog and more documentation about ALTER TABLE
include/mysqld_error.h:
  New error message
mysql-test/t/merge.test:
  Test of error conditions
sql/gen_lex_hash.cc:
  Smaller array
sql/ha_myisammrg.cc:
  Cleanup
sql/share/czech/errmsg.txt:
  New message
sql/share/danish/errmsg.txt:
  New message
sql/share/dutch/errmsg.txt:
  New message
sql/share/english/errmsg.txt:
  New message
sql/share/estonian/errmsg.txt:
  New message
sql/share/french/errmsg.txt:
  New message
sql/share/german/errmsg.txt:
  New message
sql/share/greek/errmsg.txt:
  New message
sql/share/hungarian/errmsg.txt:
  New message
sql/share/italian/errmsg.txt:
  New message
sql/share/japanese/errmsg.txt:
  New message
sql/share/korean/errmsg.txt:
  New message
sql/share/norwegian-ny/errmsg.txt:
  New message
sql/share/norwegian/errmsg.txt:
  New message
sql/share/polish/errmsg.txt:
  New message
sql/share/portuguese/errmsg.txt:
  New message
sql/share/romanian/errmsg.txt:
  New message
sql/share/russian/errmsg.txt:
  New message
sql/share/slovak/errmsg.txt:
  New message
sql/share/spanish/errmsg.txt:
  New message
sql/share/swedish/errmsg.txt:
  New message