efl_ui_radio: cleanup API

efl_ui_radio: cleanup API

This is a bit of a giant commit. However, the problem here is that
cleaning up the API went hand in hand with rewriting most of the usages.
In the process of renewing and removing old API the following was done:
- Legacy API testcases have been ported back to smart callbacks
- EO-API testcases have been ported to efl_add syntax
- weird event #defines have been removed
- Wrong constructor usage has been removed
- Ported to the new box object introduced before
- removed legacy API from efl_ui_radio
  -> no more ptr(int) q66 will do jumps of happiness
  -> no more ununderstandable group_add methods
  -> Seperated code in blocks only for legacy, and blocks only for
non-legacy

To verify this commit, you can check all the tests that have been
touched here. Additionally, the cxx example has been adjusted

ref T7867

Reviewed-by: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Differential Revision: https://phab.enlightenment.org/D9060