Revert "Upgrade to JQuery 1.11.1"

This reverts commit 60e9dfe81928eabe7f03ac0502042b0dba3058e9.

Conflicts:
	mozillians/templates/phonebook/logout.html
Use jQuery version 1.8.3.

The jQuery upgrade to 1.11 broke some client side functionality,
that's why we reverted commit 60e9df and started using v1.8.3.

jQuery >= 1.8 is a dependency of django_browserid.
[Fix bug 1032196] Fix external accounts dynamic formset handling.
Merge pull request #1007 from johngian/fix-bug-1032196

Fix external accounts dynamic formset handling.