feat(avatars): profile images

Getting there! Feel free to start looking @shane-tomlinson @pdehaan.

Still needs:
- [ ] profile-server client
- [ ] progress indicator screen
- [ ] unit tests for camera view
- [ ] unit tests for cropper widget
- [x] circular overlay on cropper
- [ ] functional tests
I'm mildly confused here.
On line 7, it's `/fonts/icons/fontello.svg?{hash}#name` but here it's `../font/fontello.svg?{hash}#name`.

The pattern's don't match. Do we have two copies of fontello.svg at different levels, or should line 17 here say `/fonts/icons/fontello.svg?blah`