* Simplify and enhance PropertyBinding Regex

* Update Regex of PropertyBinding.

* Update regular expression of PropertyBinding

* move is* properties to prototypes and remove unused ones

* rebuild

* merge dev -> less-is

* remove rebuild from PR

* convert to ES modules

* rebuild

* move shaders back into glsl files

* reinstate polyfills

* Let THREE.PropertyBinding.parseTrackName() follow code style

* Let CleanupPropertyBinding follow code style more

Refs #9057 : Fix test for property existence in property binding in the case if property is a false boolean or a numeric equal to zero (#9064)

Make the parseTrackNam()e regular expression more lenient to accommodate
bone names that contain '-' characters.

allow for PropertyBindings to bind/unbind.  PropertyBindings are reference counted by Mixer for efficiency.

only update scene graph values if actually different, only call triggerDirty if values changed.  Use bone names.

fix bugs in KeyframeTrack.optimize/validate.  Expand capabilities of PropertyBinding bind to work with bones.  fix bugs with JSONLoader animation converter.

memeoization of lerp.  add optimize, trim, validate, sort to KeyframeTrack.  Create separate AnimationClipCreator class to get demo code out of ThreeJS src/ directory.

optimization - stage one.  Reduce temp memory allocations, cache PropertyBinding.apply logic as a closure.