[MediaConsole] Added methods for creating servers

Two new methods have been added to the UPNP class, server_from_name and
server_from_udn.  These methods can be used to construct Device objects
from UDNs or friendly names, which is typically easier than using
the d-Bus path, which is long and changes from one invocation of
dLeyna-server to the next.

Signed-off-by: Mark Ryan <mark.d.ryan@intel.com>
[Property] Support of DLNA.ORG_CI, DLNA.ORG_FLAGS and DLNA.ORG_OP

Fix https://github.com/01org/dleyna-server/issues/54

Add 3 new properties to Resource.
As for other Resources properties, they are also directly
available in MediaTiem2 or MediaContainer2 item by using the
algorithm for selecting resource, given in the section
"Transcoding and org.gnome.UPnP.MediaItem2".

Signed-off-by: Ludovic Ferrandis <ludovic.ferrandis@intel.com>
[Bug] Add a Rescan method to Manager interface

- Resolves bug #4
- Make use of new API gupnp_context_manager_rescan_control_points()
- Documentation updated.

Signed-off-by: Sébastien Bianti <sebastien.bianti@linux.intel.com>