Moving libbluedevil to unmaintained

[David Rosca]

Hi all,

with Bluedevil now ported to BluezQt and with regard to no more
kdelibs4 Bluedevil releases, I will no longer work on libbluedevil.

Porting from libbluedevil to BluezQt is pretty straightforward (only
problem might be async initialization), so I suggest to anyone still
using libbluedevil to switch to BluezQt.

If there are no objections in next 2 weeks, I will ask to move
libbluedevil to unmaintained.

David