Remove Unused to also Remove Empty Bins

[Mat_TTM]

Hi!

The idea is simple:

The "Remove Unused" feature, to also remove any bins that become empty during this process.

When you're tidying something up, this would really help to speed up this process, instead of just leaving lots of empty bins around, keeping the project just as clogged as it was before.

This could also be a handy addition to the "Consolidate Duplicates" feature.

If someone comes and tells me this already exists that would ALSO be great 8)