[lipstick] Fix crash on close

When destroying LipstickCompositor ~QQuickWindow() is called after
~QWaylandQuickCompositor(), so changes to the items in the window may end
up calling code such as LipstickCompositorWindow::handleTouchCancel(),
which will try to use the compositor, at that point not usable anymore.
Add a protocol to be used by Alien
Use a surface operation to enable sending oom score events
Merge pull request #214 from giucam/alien

[lipstick] Introduce a custom wayland protocol for alien clients
Add missing build require
Merge pull request #213 from giucam/segfault_on_close

[lipstick] Fix crash on close
[lipstick] Fix use after free when closing the alien client
Merge pull request #215 from giucam/fix_crash

[lipstick] Fix use after free when closing the alien client
[lipstick] Remove disconnectRef and listen availableWinIds changes

LipstickCompositor availableWinIdsChanged signal is connected
when a value of __winref window property is read for the first
time.