Moving MyAvatar specific code out of Avatar and into MyAvatar.
MyAvatar doesn't need to be a friend of its base class Avatar.
Removing AvatarManager::clear() as unecessary during class destruction.
Moved LookAtTargetAvatar stuff from AvatarManager to MyAvatar.
Moving headMouse, transmitter, and touchYaw/Pitch stuff into MyAvatar.
Merge branch 'master' of ssh://github.com/highfidelity/hifi into cleanup
Merge branch 'master' of ssh://github.com/highfidelity/hifi into cleanup
Merge branch 'master' of ssh://github.com/highfidelity/hifi into cleanup

Conflicts:
	interface/src/Application.cpp
Merge pull request #1823 from AndrewMeadows/cleanup

cleanup: moving stuff out of Application and AvatarManager into MyAvatar