cmd-line-utils/readline from the commercial distribution
 - fixed some copyright headers so mysql-copyright can process them


Build-tools/mysql-copyright:
   - remove the cmd-line-utils/readline directory from the commercial
     distribution
   - make use of more builtin Perl functions instead of forking 
     subprocesses
include/my_pthread.h:
   - fixed copyright header
sql/filesort.cc:
   - fixed copyright header
sql/gen_lex_hash.cc:
   - fixed copyright header
sql/item.h:
   - fixed copyright header
sql/item_cmpfunc.cc:
   - fixed copyright header
sql/records.cc:
   - fixed copyright header