So far this new module contains:
* Display
* OutputInterface
Display manages the server socket and server event loop. In general it's
the entry point to any part of the server.
OutputInterface is the abstraction for the wl_output interface on server
side. An OutputInterface is created through the Display.
The auto tests for ConnectionThread and Output are adjusted to use the
internal server instead of starting Weston. Especially the Output test
could be extended to test much more as we have absolute control over
the server now.
At the same time adding an autotest for the Output, moving the listener
into the Output class and providing enums for Subpixel and Transform.
KWin now requires wl_ouput interface version 2 as that allows us to emit
the changed signal in a better way.
The unit test is not yet capable of testing everything, we need a mock
Wayland server which is more flexible.