ActionView now takes the attachment point that the view is placed in,

for easy lookup and for registration.
The views are no longer stored in one long list. Instead, they're

organized by the attachment point. This will ultimately allow for

multiple views for the same action in different attachment points, and

to enable looking up the correct action within the right attachment

point.

Unit tests passed.
Tested that all actions, including menus and Quick Access actions,

all worked and expected.
Tested that Quick Access actions could be customized.