Switches AVM1Utils.addEventListenerProxy to a native implementation
Optimizes parsing and fixes application of AVM1 ClipEvents

And moved their application to avm1lib. Before, it was partly in FrameDelta#_initialize, partly in the late Sprite#_initAVM1Bindings.

This also fixes the mapping of some of the ClipEvents to equivalent AVM2 events. Some aren't trivially mapped, so more work has to be done there. Those will show a warning at least when they're used.
Adds new test for mouse events on nested AVM1 objects and reactivates some existing tests

The existing tests where disabled before the nat branch merge and then forgotten about.