build: Don't conditionally omit files from distribution
tests: Don't run session-long dbus daemons for tests

They require a tty or X11 displays, thus are not suitable for headless runs
(such as in mock). Furthermore, they die with the tty or X11 session, which
is somehow late -- a lot of them may accumulate. Let's kill them right away.
contrib/rpm: Run make check
contrib/rpm: Use bconds