Add Ember pre4 to components
Remove some extraneous legacy stuff from the TrackView.
Add generic 3D view base class.
Minor cleanup
Rename World's add() argument from obj to node, to be consistent with ThreeView's interface.
Add TODO note for later.
Add convenience method to get the Note at a given string and fret index coordinate.
Add method to clone a Target with a displayTime offset.
Change FrequencyTargetView to inherit from ThreeView
Add Renderable mixin to help with views for composite models.
Add model attribute placeholder
Convert "target" attribute to "model"
Add some position and dimension fallbacks
Rename FrequencyTargetView to FrequencyTargetThreeView
Remove FrequencyTargetView artifact, update build list
Update build list with Renderable and ThreeView
Add Renderable mixin
Revert "Add Renderable mixin"

This reverts commit fc3d7db4a23301781e65f959859119900b89ce98.
Revert "Revert "Add Renderable mixin""

This reverts commit 49f89fb3b26a911957dd6985f18c51ee344e3883.
Formatting