Batch buffer update

Improve pipelining: submit buffer updates in order that they will be
rendered before they are rendered to allow for them to complete before
the data is required.

@benadams Oh wait, is this because the strides stuff?

/cc @benadams

Fix build errors (three.min.js)

handle empty geometry in BufferGeometry.fromGeometry

SphereBufferGeometry

Changed some examples to use SphereBufferGeometry
Added coord getters to Buffers
Changed Matrix apply to work with both Interleaved and Regular Buffers

reduce redundant texture binds

Cache currently bound and active textures and move texture binds to WebGLState

Fix for Firefox WebVR (again)