Start working on Pebble SSO. Works if you look for it.
Started account migration logic/UI.

Still need to handle:
- disabling legacy logins after migration
- AuthAlreadyAssociated exceptions.
Handle merging more correctly.
Added a setting for developers without an OAuth server handy.
Added sign out and sso sign up links.
Merge branch 'pebble-sso'
Copy relevant project settings to project instances.
Merge branch 'bugfix/copy-template-settings'. Fixes #28.
Drop UserVoice (fixes #25).