WINTERMUTE: Adds workaround flags and uses a workaround flag to fix #6647

Behaviour of BaseSprite::reset() changed in WME 1.8.6.
5MA and possibly other games ship with pre-1.8.6 WME, and depend on the old behaviour.

We then set up WME-specific workaround flags and use one of them to makr a game as depending on the old behaviour.

I had a lot of guidance from @fuzzie on this - but don't blame the poor lady if it's still ugly, the ugly parts are all mine.

If you prefer a less invasive (but imho rather ugly) solution there's my branch fix_cat_hackish: 
https://github.com/tobiatesan/scummvm/compare/fix_cat_hackish

It simply if()s to look at the game name.