-Removed Cheat menu and replaced it with "Cheats..." menu item in the Options menu.
-Modified alert_message and confirm_message so they handle line wrap of the message internally, so now it's no longer necessary to insert newline chars into strings passed to alert_message and confirm_message.
-added list_find_node utility function to util.c.
-added utility functions to create/delete cheat structures for use by the gui.