Django 2.0 and older make use of some imports from the collections

module that no longer exist on Python 3.10 and higher. When running with

these combination of versions, Django Evolution will patch collections

to bring back these old imports, allowing Django to work once again.
This is a port of similar code from Djblets (which can probably be

removed now), and will only apply when running on Django 2.0 or older

with Python 3.10 or newer.

Unit tests pass.
Used Review Board (without the Djblets workarounds active) to test

this patch. Verified that the collections module had the legacy

imports on Python 3.10.