Blender Git Commit Log

Add an option to free scene without doing id-counters

This is similar to some other datablocks. Mainly applies to collections,
so freeing scene does not involve changing any non-directly owned data.

There are two main usecases foreseen for the future:

- Less CPU ticks on bmain free, where everything is freed anyway and
there is no need to preserve id counters.

- Easier freeing of temporary data, including data which is used by
depsgraph's copy-on-write mechanism.

Neither of those are currently implemented, but will be shortly.