Do not bundle liquidsoap library

I think the code was bundled into legacy upstream before it was
readily available in liquidsoap proper. These snippets are now
maintained at https://github.com/savonet/liquidsoap/tree/master/scripts.

On all distros I checked these scripts are installed to /usr/bin/liquidsoap
by the corresponding package. Liquidsoap loads them from there by
default.

By not bundling this we will be ready to profit from new features and
bugfixes in liquidsoap that is expected to land on opam soon. We'll
need to figure out how to get debian and others updated when that
happens.

python_apps/pypo/setup.py

@@ -38,7 +38,7 @@ setup(name='airtime-playout',
       author='sourcefabric',
       license='AGPLv3',
       packages=['pypo', 'pypo.media', 'pypo.media.update',
-                'liquidsoap', 'liquidsoap.library'],
+                'liquidsoap'],
       package_data={'': ['*.liq', '*.cfg', '*.types']},
       scripts=[
           'bin/airtime-playout',