Revert "don't print version string as "favourite spell" if there is none"

This reverts commit eed9eca61cbab8f134d82d9a2cbe3b7e31eedbb8.
don't show tooltips when the mouse is disabled
BG2: reset portrait when starting over with character creation
fix highlighting of moused-over regions for games other than BG1
rename GF_CLEAR_UNUSED_AREA to GF_INFOPOINT_DIALOGS

Also invert its meaning. Makes much more sense this way around.