Deprecation Guide for mouseEnter/Leave/Move events in {{action}} modifier

As mouseenter, mouseleave and mousemove events fire very frequently, are rarely used and have a higher implementation cost, support for them in Ember's EventDispatcher has been deprecated. As such these events should not be used with the {{action}} modifier anymore.

Before:

<button {{action "handleMouseEnter" on="mouseEnter"}}>Hover</button>

After:

<button {{on "mouseenter" this.handleMouseEnter}}>Hover</button>