some preparation for adding hand state to avatar interactions
renamed "bodyPosition" to "position". (This corresponds to the position of the avatar on the ground, where y=0). I will next add a new "getBodyPosition" which returns the avatar's center of gravity - is useful for certain purposes, such as setting collision volumes, etc.
made lots of changes in the logic of how my avatar encounters other avatars and detects hand state
Merge remote-tracking branch 'upstream/master'
Merge pull request #118 from Ventrella/master

prepared for hand state changes, and also renamed bodyPosition to position