[SPARKL-44] Multiple spinning wheels were eliminated.
[CLEANUP] Removed unused js/png/img resources.
[CLEANUP] Removed hidden and unused plugin filters.
[CLEANUP] Removed unused and hidden element sort component (functionality already provided by table headers).
[SPARKL-81] Updated URL of call to CFR endpoint (was using 4.8 syntax)
Merge pull request #28 from marcovala/5.2

Cherry pick from master for 5.2