For these standard motions, the viewer likes to very frequently
flood-call startMotion/stopMotion sometimes, which at the very
least needs a LLUUID lookup in a std::map. In particular, this
is done for two of them for every avatar in the sim every frame.
This code makes it possible to test if that makes sense by
merely doing a bit test.
Conflicts:
indra/llcharacter/llkeyframemotion.h
