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.
Cache AVM1ActionsData for ClipEvent handlers on first use

As Yury points out, it's not useful to compile these over and over again.
Fixes regression in AVM1 context initialization

Regressed in one of the last few commits and caused two tracetests to fail.
Give PromiseWrapper a `then` method
Cleanup in Loader.ts

Some dead code-removal, some reordering of functions.
Delay committing Loader updates until the right point in the event loop

This introduces a bit of added complexity, but amazingly only a net 4 new lines of code.
Move SWFFile into its own .ts file and into the Shumway.SWF module

Because it really doesn't belong into FileLoader.ts
Remove useless registerSymbol method in LoaderInfo
Support initialization from Uint8Array in source instead of special-casing BinarySymbol in ByteArray initializer
Makes embedded ByteArrays and Loader#loadBytes work again