move head rotations to new HeadData class to be used for transmission
move _lookAtPosition to HeadData class
code review comments, cleanup Avatar constructor
type squishes in AvatarData
Merge pull request #362 from ey6es/master

Fix for matrix stack bug that was breaking Oculus rendering (if nothing else).
Merge pull request #361 from birarda/head-changes

add a HeadData class to reduce redundancy for head member variables
move _leanSideways and _leanForwards to HeadData
Use glDrawRangeElements, which indicates the range of used indices.  It may or
may not make a difference in performance, but it won't hurt.
Merge pull request #363 from birarda/head-changes

move lean sideways and lean forwards to the head data class
lazy allocation of HeadData in getBroadcastData
Merge pull request #364 from birarda/master

lazily allocation of HeadData in getBroadcastData
Merge branch 'master' of https://github.com/worklist/hifi
Added basic capsule/sphere collisions between avatar and voxels.