gatt: Add GATT service to the local database
gatt: Add GATT service to the local database

This patch creates GATT service attribute based on its GDBusProxy
object, and inserts the declaration to the local database.

pstglia/external-bluetooth-bluez,pkarasev3/bluez,silent-snowman/bluez,mapfau/bluez,mapfau/bluez,pstglia/external-bluetooth-bluez,silent-snowman/bluez,ComputeCycles/bluez,pkarasev3/bluez,mapfau/bluez,pkarasev3/bluez,silent-snowman/bluez,pstglia/external-bluetooth-bluez,pkarasev3/bluez,mapfau/bluez,ComputeCycles/bluez,ComputeCycles/bluez,pstglia/external-bluetooth-bluez,silent-snowman/bluez,ComputeCycles/bluez