Port UserProfileAvatarSettingsManager from Review Board

Review Request #9951 — Created May 16, 2018 and discarded — Latest diff uploaded

Information

Djblets
release-1.0.x

Reviewers

This patch is a direct port of the UserProfileAvatarSettingsManager
from Review Board with a number of added unit tests.

Ran unit tests on Django 1.6.11 and Django 1.8.19.