GTK: generate 'CD lid open/close event' automagically when switching ISO images. No need to press F9 & F10 anymore when a game wants to change CDs.

git-svn-id: https://pcsxr.svn.codeplex.com/svn/pcsxr@84880 e17a0e51-4ae3-4d35-97c3-1a29b211df97