Merge pull request #75 from fedora-infra/libravatar_filter

Libravatar filter
Add the avatar on the pending ACLs page
Merge pull request #74 from fedora-infra/libravatar

Add libravatars to some of the UI.
Add a dedicated method to approve all the pending ACLs
Add unit-tests for the method to approve all the pending ACLs
Add a dedicated method to deny all the pending ACLs
Add unit-tests for the method to deny all the pending ACLs
Add CSRF protection on the Approve/Deny all pending ACls
Adjust the unit-test to validate the CSRF protection for Approve/Deny all pending ACLs
Add the approve and deny all pending ACLs button on the pending ACLs page

Fixes https://fedorahosted.org/pkgdb2/ticket/27
Small css enhancement to space a little the approve/deny all pending ACLs buttons