Revert "lua-factory: port grl-radiofrance.lua to the new lua system"
Revert "lua-factory: port grl-radiofrance.lua to the new lua system"

This reverts commit 93547ac94797cdea6670b0d458e838bcdb578f77.

But keeps grl.fetch callback as function instead of string

https://bugzilla.gnome.org/show_bug.cgi?id=763046

GNOME/grilo-plugins,MikePetullo/grilo-plugins,GNOME/grilo-plugins,jasuarez/grilo-plugins,MikePetullo/grilo-plugins,grilofw/grilo-plugins,grilofw/grilo-plugins,MikePetullo/grilo-plugins,jasuarez/grilo-plugins