mostly working, but some blinking when setting glow
added some unit tests for ModelTree
more work on optimized storeModel()
optimized findModelByID
hacking more on the modelID to element map
improve ModelItemID to ModelTreeElment map to not require rewriting when locel model ids are assigned values
added comments about recursion vs direct access to model items
removed old dead code
added some performance tests

Conflicts:
	tests/octree/CMakeLists.txt
	tests/octree/src/ModelTests.cpp
	tests/octree/src/ModelTests.h
	tests/octree/src/main.cpp
Merge branch 'master' of https://github.com/worklist/hifi into experimentalStoreModel

Conflicts:
	tests/octree/CMakeLists.txt
	tests/octree/src/ModelTests.cpp
	tests/octree/src/main.cpp
added some more tests
Merge branch 'master' of https://github.com/worklist/hifi into experimentalStoreModel
added more timing details to model tests

Conflicts:
	tests/octree/src/ModelTests.cpp
seed random generator to make tests reproducable
octree tests tweaks

Conflicts:
	tests/octree/src/ModelTests.cpp
	tests/octree/src/main.cpp
added more debug
added bestFit support for testing add
tweaks
add deleteModel unit test
implement version of deleteModel that correctly marks tree as changed