Fix encoding with Movit and WebVfx used together.
Permit loading MLT XML that uses GPU and CPU filters.
Make projects more portable by not outputting root attribute in XML.
Fix saving initial project with relative paths to assets.
Let double-click on a shot in timeline open it in source viewer.
Fix using pointer to temporary string.

The QString was destroyed with QFileInfo after the pointer was obtained.
Move filter reordering logic from the view to the model.

Setting things up to limit filters that are only supposed to have one instance.
Some filters are limited to a single instance per producer.
Have the ListView interact with the model directly rather than through the controller.

Setting up to give the timeline to the attached filters model.
Synchronize filter view when filters are manipulated by the timeline.