Blender Git Loki

Fix modifiers stack not recalculated when mapping requirements change

Reported by pixaal on irc, basically reproducable by inserting bevel
modifier on cube and entering/exiting texture paint mode.

Now object stores last needsMapping variable as well as customdata mask.

Also now texture painting only needs mapping when we are in texture
paint selection mode, so modifiers that don't support mapping can still
be used to paint now.