Notifications: Fixes images from not loading in the follow detail view until forced to redraw.

git-svn-id: http://ios.svn.wordpress.org/trunk@4039 7d847f7c-ffe1-4a24-85be-b788d016d96a
Resize the (now larger) gravatars we get from the REST API down to the size we need. Fixes #1556

git-svn-id: http://ios.svn.wordpress.org/trunk@4040 7d847f7c-ffe1-4a24-85be-b788d016d96a