1. Added support for loading sub-objects in .OBJ into a generic
attribute.
2. Added missing mesh_are_equivlent classes needed for certain unit
tests.
3. Updated javascript decoder reflecting our latest changes + added
support for GeometryAttribute::custom_id() method.
4. Added checks for valid quantization bits to our draco_encoder app.
1. Add 'use strict'to example Javascript.
2. Small fixes to README.md.
3. Fix Draco compiler flag tests.
4. Fixed issue when number of quantized bits was to large.
5. Changed StartDecoding to return a value.
6. Check that num of attributes are not less than 0.
7. Check that the number of attributes is a valid value.
