Fix issue: 69050.  Deletion of a math function without cleaning up the next node that _might_ be a function render nodification would break the math.  Also adds test case to EditTest.
Fix a bug with the isEmpty setup.
Fix up the test case to actually test the correct thing.
Initial start for restricting the key press entries.
Add in code that handles the color selection insanity.
Provide content restriction options to the user in terms of what buttons the user can use to type.
Ensure the tests are actually enabled for the restrictKeys entry.  The existing container ID test now really has all the bells and whistles.
Ensure that if we provide serialization support it will not stomp the function that is defined.
Do not polute the default key information in CFG serializations if we are using a CFG default.
Also make d delete the item currently selected (only happens if d is not a valid button, or you don't have TeX entry enabled.
Merge branch 'master' into gh-pages