Issue #3486893, #3478484, #3483064, #3415662, by joshua1234511, richardgaunt, fionamorrison23, febdao, gargsuchi, sonam.chaturvedi, mwjansen, alex.skrypnyk: Add opt-in for controlling what form elements are rendered via civictheme system.

Issue #3486893, #3478484, #3483064, #3415662, by joshua1234511, richardgaunt, fionamorrison23, febdao, gargsuchi, sonam.chaturvedi, mwjansen, alex.skrypnyk: Add opt-in for controlling what form elements are rendered via civictheme system. #1105