FLUID-4939: test case for circular grades.

Added a test case that shows the issue when a component adds a grade, that also contained the component itself as a grade. The init functions here are also fired multiple times.
FLUID-4927: refactored TextfieldSlider

Refactored textfieldSlider to use invokers, have an afterRender event, and added a rednerOnInit option. The tests stll all pass and added a couple more to test the afterRender event.
Merge remote-tracking branch 'cindy/FLUID-4927' into FLUID-4927-b
FLUID-4927: added textfieldSlider to dependencies

Added TextfieldSlider.js to the UIO dependency file.
Merge remote-tracking branch 'cindy/FLUID-4927' into FLUID-4927-b
FLUID-4939: Fix for fresh test case involving circular grade references (which previously had undefined behaviour status), some linting
Merge remote-tracking branch 'cindy/FLUID-4927' into FLUID-4927-b
Merge remote-tracking branch 'amb26/FLUID-4939'

* amb26/FLUID-4939:
  FLUID-4939: Fix for fresh test case involving circular grade references (which previously had undefined behaviour status), some linting
  FLUID-4939: test case for circular grades.
FLUID-4908: Fixed the failing FullPreviewUIOptions-test.html to replace the use of the setTimeout in wait of toc rendering with registering the listener to a proper afterRender event.
Merge branch 'master' into FLUID-4908
Merge branch 'FLUID-4908' into FLUID-4927