Tweepy and Whoosh upgrades aren't so urgent
KanisaUserCreationForm -> KanisaAccountCreationForm
Replacing some things which directly refer to the user model
Swapping out foreign key to the stock User model
UserChoiceField -> AccountChoiceField
Swappable users for the service planning form
Replacing User with get_user_model
Tests now support swappable users
Fix a couple more places to use get_user_model
Tidy up imports
Switch User to get_user_model()
Swap out Django's default user for our own

This will help with supporting user avatars, and other
things we might want to do in future.
Use user familiar names in a few contexts
URLs should have trailing slashes
Give the MP3 download URL a .mp3 extension

Hopefully that'll make it more obvious what will happen if
you visit that URL (mostly for robots).
Uncomment and re-order, to make it clearer what can be imported
The depth keyword to select_related is deprecated
Add TODO
Shuffling TODO items
Tests for account activation