Profile screen can now be used to view other people's profiles. #10

Many changes!

Temporarily removed unused sections (description, points, checkins), for future reference they can be seen here: https://github.com/mrienstra/barchat/blob/a95aab0cbe/src/script/screen/profile.jsx#L43-52

New `remote.fb.getProfile` method.

Changing from `basic_info` permission to `public_profile` permission, as per https://developers.facebook.com/docs/apps/changelog#v2_0_login

`_remote.parse.loginWithFBAuthResponse` method: combined 2 FB API calls into one.

Other minor changes.

Adding `handleProfileChange` handler to direct clicks on user photos to the profile screen.

Extended `handleProfileChange` function.

Plus minor plumbing to support wider usage of profile screen.