* Prepare native sets API for exposing into public. This needs to have
  a bit of thought as we probably will want to expose only read-only
  API. Also we probably don't want to expose every gory detail of sets
  implementation. For GObject introspection purposes the exposed
  classes will need to be boxed into GTypes.

* Merge native profile backend into GUPnPDLNAProfile and
  GUPnPDLNAProfileGuesser. That way we can get rid of
  GUPnPDLNAProfileGuesserImpl and some backend files, expose profile's
  restrictions and rename GUPnPDLNANativeFoo into GUPnPDLNAFoo. Also
  we could extend gupnp-dlna-info-2.0 and gupnp-dlna-ls-profiles-2.0
  to show more information about DLNA profiles.

* More about extending tools - gupnp-dlna-info-2.0 could show DLNA
  profiles restrictions (likely) and discovered metadata attributes
  (bit unlikely, but dunno). gupnp-dlna-ls-profiles-2.0 could show
  restrictions of listed DLNA profiles.

* Write a GStreamer-only utility for creating a GstEncodingProfile
  from GUPnPDLNAProfile. That could be easily done when above points
  are done.

* Bring the tests back to life. And make them being run on make check.

* Don't export all functions out there. There should be some linker
  flag that either takes a regexp for functions to export or takes a
  file listing them. Otherwise using G_GNUC_INTERNAL for every
  function not to be exported will be tedious.

* Generate Vala API.

* Read TODO.old for some ideas.
