Renamed tree accessor module.
Moved tree implementation to tree package.
Fixed division operation and changed sematics of normalization to immutable on vector.
Moved vector unit test to test package in util.
Removed maya specific import on plane coordinate system module.
Created own module for OBJ mesh private implementation.
Added mesh accessor class.
Removed author tag in package init file.
Sliced mesh accessor unit test modules to make each module contain the tests for one class.
Fixed import statement in OBJ importer to match new private OBJ mesh implementation module.
Fixed imports to match change in tree package module names.
Fixed import to match new private OBJ mesh implementation module.
Fixed imports in reload hack.