fix broken speech bubble display in chat. caused by
r1a6b9a98147c one line was forgotten when moving some code
fix TryPlaceOnLand's ambiguity/messup wrt to making terrain indestructible (had boolean parameter for indestructible AND landflags parameters that could contain lfIndestructibly)
placeSprite accepts any amount of landflags now; further WIP wrt cleanup/fixing
make enums crash-safe. and other fixes
WIP: PlaceSprite for lua API. also changed PlaceGirder so that it will return true/false for whether placing was successful too
fix possible engine crash that a lua script could cause by passing an invalid geartype to addgear