fixed a bug with cheat code file handling

For easy mode if cheat exist it will not be automatically overwritten when a different one is available in the database. To overwrite existing cheat press + key on the main screen.

Fixed a bug where cheat code file would be renamed to .old even when there isn't a cheat code available from cheat database when replacing cheat with file from database is enabled

Changed the bit ordering of P (See release note of 3.8.08). It is now reversed for better run time efficiency in pointer search.