Geoclue hardening

[Bastien Nocera]

Hey,

Right now, Geoclue feels a bit brittle. Not that it crashes, but
sometimes it stops being useful for use with some devices.

My first problem was that it only loaded GPS device options on startup,
and because it doesn't monitor clients, it would never exit. So unless
you restarted your session, you'd never be able to use your newly setup
Bluetooth GPS device.

I've made a patch for that case:
http://bugs.freedesktop.org/show_bug.cgi?id=22380

We would need some changes to the gpsd and gypsy providers to handle
settings the options after startup.

The second problem was the horribly fragile code copied in a few modules
to get the MAC address of the AP:
http://bugs.freedesktop.org/show_bug.cgi?id=22378

Opinions needed on that.

Finally, if a few people with GeoClue API experience could take a look
into the patch I posted at:
https://bugzilla.mozilla.org/show_bug.cgi?id=485472

Cheers