Blender Git Loki

Include "static override rules generator" operation into new depsgraph.

Note that this is dummy empty placeholder for now!

Idea here is that depsgraph is best place to generate our override rules
based on data changes. That way all tools in Blender keep working as
usual, on local data, and overrides are generated when needed just
before IDs get actually evaluated.

Depsgraph has key advantage of only running over *changed* data-blocks
already.

Not sure this is actually valid idea, but for tests will do the work.
If we want to keep it, we'll have to find a way to prevent this running
too often though, especially not during most animation-triggered
evaluations.