As this was the last step in the base constructor, it could be
done in each menu type without the callback and extra code.
The only reason this existed was to allow menu "sub classes"
that override this function. However, since this was rewritten,
it was no longer used, so for the sake of simplicity, I remove
this feature.
Radical is a model-view framework. There is a common API to
set data, then view modules to display it. Those modules have
been rewritten on top of new APIs.
Not all features are yet re-integrated, most are. Future commits
will address the various regressions and missing features. This
time, the code should be maintainable. The whole separation of
concerns analysis has been re-done. Allowing code de-duplication
and generalization.
The API remain the same, only `set_menu` has changed a little to
allow merging the 2 sub-menu code paths.