Fix WAV file support

The previous implementation assumed the file only contained RIFF, WAVE,
fmt, and data chunks.  It is valid for other chunks to appear, so I
updated it to skip any chunks until it finds the "data" chunk.
Add playSoundWave.js
removal of unused getNeckRotation()
Try rounding to nearest texel unit to reduce shimmer.
Merge branch 'master' of https://github.com/highfidelity/hifi
remove unused Head::_gravity data memeber
merge upstream/master into andrew/inertia
move hand/arm stuff from Model to SkeletonModel
move face/head code from Model into SkeletonModel
fix bug -- negate logic around invalid joint index
simplified hand index constants
Use multisampling on the shadow maps for the voxels, too.
Merge branch 'master' of https://github.com/highfidelity/hifi
Merge pull request #2935 from AndrewMeadows/inertia

cleanup: move avatar specific stuff from Model to SkeletonModel
Merge branch 'master' of https://github.com/highfidelity/hifi
Fix for Windows build failure.
Merge pull request #2936 from ey6es/master

A couple more shadow tweaks: reduce "shimmer" by moving in texel increments, use multisampling on voxels as well as models.
Merge pull request #2937 from huffman/19714

Code Review for Job #19714
Job #19694 - Add option for larger number of frames to the audio scope display
Merge pull request #2938 from matsukaze/master

Job #19694. Add option for larger number of frames to the audio scope d...