Author: Sam Hemelryk
MDL-21676 user: Implemented support for Gravatar profile pictures
Big thanks to the developers who put effort into this improvement:
* Jonathan Robson <jonathan.robson@remote-learner.net>
* Jonathan Harker <jonathan@catalyst.net.nz>
http://git.moodle.org/gw?p=moodle.git;a=commit;h=4125bdc139eb659595fd6d017c8ae083041fb262
http://github.com/moodle/moodle/commit/4125bdc139eb659595fd6d017c8ae083041fb262