The "config" global variable is set to the value specified in the
--lua-config VLC option. For example:
---lua-config "rc={a='test',c=3},telnel{a='hello'}"
+--lua-config "rc={a='test',c=3},telnet={a='hello'}"
config will be set to {a='test',c=3} in the rc interface, to {a='hello'}
in the telnet interface and won't be set in other interfaces.