Fix unicode username bug and use celery retry to get CourseEmail

 Remove username from email footer.
openended problems now do an ajax call everytime they are loaded
Merge branch 'giulio/peer-grading-style-release' into edx-west/release-candidate-20130729

Conflicts:
	common/lib/xmodule/xmodule/js/src/combinedopenended/display.coffee
Merge branch 'feature/kluo/bulk-email-squashed' into edx-west/release-candidate-20130729