Rename RoundFileSrc->SrcWavFile & GnomeVFSMP3Src->SrcMP3Stream, drop multiverse.

Three reasons for this:
* Code simplification; renaming these classes and files makes their functionality more obvious.
* Reduction of dependencies (~8MB of disk space); we don't need the _gstreamer0.10-fluendo-mp3_ and _gstreamer0.10-plugins-bad-multiverse_ packages (as far as I can tell), using the more standard `souphttpsrc` and `filesrc` GST plugins means we don't need _gstreamer0.10-gnomevfs_ package. Also,  _gstreamer0.10-gnomevfs_ is not available for Ubuntu 14.04 LTS (see #150). Which leads to the next point:
* Another step towards Ubuntu 14.04 and Python3 (see #102)

Note: I've also added `killall python` to the end of the development `./runserver.sh` script to stop the _rwstream.py_ audio streams when runserver exits.

I've tested and retested this. It seems to be working. It changes the gconf errors (See #90), but doesn't *seem* to affect functionality. Errors are now:

   ** (rwstreamd.py:12661): WARNING **: Error spawning command line `dbus-launch --autolaunch=96930403cd315dbc6536a59a00000103 --binary-syntax --close-stderr': Failed to execute child process "dbus-launch" (No such file or directory)

Maybe we need dbus-launch? It's easy to add back, but it still causes warnings.