Little, easy improvements

Here's a list of selected improvements that we'd like to make to Django. The easiest fixes can be found via the "Easy" tickets link on ​dashboard.djangoproject.com.

If you don't feel like writing Python, you can always help with patches needing documentation or, between coding and documenting, you can give a hand with the patches needing tests, or patches that need some other improvement.

Below are some more substantial changes that have been started but abandoned and could probably be finished without too much difficulty.

Ticket	Description
#21429	​Fixed #21429 -- Added builtin logging support to BaseCommand.
#11154	​Fixed #11154, #17904 -- Added creation of proxy model permissions
#10827	​Fixed #10827 -- Made create_permissions() clear the ContentType cache.

Feel free to reach out to Tim Graham (timograham on #django-dev IRC) if you have any questions about these tasks.