code: function CompareRuler (annoModel, rulerLocation, rulerOverview, rulerStyle) {
  		mRulers.Ruler.call(this, annoModel, rulerLocation, rulerOverview, rulerStyle);
  	}
docs: Creates a new ruler for the compare editor.
  @class The compare ruler is used by the compare editor to render trim around the editor.
  @name orion.compare.rulers.CompareRuler