This is a cleaner way to interface with the remote pipewire daemon.
The WpRemote base class can be subclassed also for interfacing
with other daemons (hardware-specific managers, etc)

This is implemented in a slightly hacky way, we register the GMainLoop
as a global object and use it from the module to quit the daemon.
This is bad design because the module assumes it is loaded inside
our daemon.

In the future, this should change. It looks like we should have an
object that tracks the state of PipeWire and main() should track
state changes of that object and decide what to do.

This allows loading of config and modules when deployed in
the target system without setting environment variables.

After discussing things at the AGL May 2019 F2F meeting
and reflecting on the initial design of WirePlumber,
it became clear that it needed a fresh start.

glib log domains are not like the gstreamer ones, where you can enable
many of them with a wildcard, therefore it is not particularly useful
to have different ones per file