[PLUGIN-MOVE] xingmux: move to -good or -base

Submitted by Tim Müller @tpm

Link to original bug (#792554)

Description

+++ This bug was initially created as a clone of Bug 774252 +++

Just making a new bug for the outstanding element which is xingmux.

I'm leaning towards moving it to -base actually, I'd like a tags plugin there and then also move id3mux there and id3demux and a future apemux and an mp3mux bin that's xingmux ! id3mux.