Added docs to UI.
Fixed error checking in behavior so it happens before crash.
Added ability to create objects with behaviors, and made GameObject final to avoid accidental errors.
createBehavior now returns a reference to the created behavior, get returns it in the correct type, fixed docs in gameobject.
Fixed returns of createBehavior.
Fixed returns in the other createBehavior.
Fixed non-shared return type in Behaviors.get.
Fixed default materials
Cleaned up assets code.
Dropped shared like an ugly baby.
Fixed a unittest failure.
Removed some more casts.
Merge branch 'release/v0.7.0' into develop
Merge branch 'develop' into feature/DropShared

Conflicts:
	source/components/behavior.d
	source/components/material.d
	source/core/gameobject.d
Cleaned up some documentation.
Temporarily fixed robot crashes and small wolf bugs.  Need to implement a more general animation solution.
Merge branch 'develop' into feature/AnimationSystem
Removed unnecessary logs and removed tabs.
Merge pull request #178 from Circular-Studios/feature/AnimationSystem

Fix robot and wolf animations
Fixed typo where we only cleared meshes.