A pile of changes to help integrate the pud v2. Mainly, do a boatload of QAction -> PopupDropperAction for all actions used in CustomAtionCababilities.
The custom ations of any track are now also added to the pud.

Also make a small addition to PopupDropperAction to make it a more seamless drop-in replacement for QAction.

Now starts the big task of getting ( and adding ) nice svgs for all these ations.

This commit does lead to a few regressions in some context menus, especially regarding missing divider lines.
These will be readded.