Add hybris wlan device type

This device will handle wifi devices using the Android HAL through
libhybris.
Use hybris device for wifi in the arbitrator
Merge pull request #9 from alfonsosanchezbeato/hybris-dev

Hybris support for wlan devices
Properly attribute Canonical copyrights
urf-utils: shorten killswitch constant strings

Shorten KILLSWITCH_STATE_* strings to reduce length
of some log messages in order to make logs easier
to read.
UrfConfig: add support for prev-soft state

The prev-soft state is used to preserve the state
of a killswitch when flight-mode is enabled.  This
allows the state to be properly restored when flight
mode is disabled and urfkill may have been restarted.
UrfDevice: fix connection & object_path code

Change urf_device_register_new() to accept object_path
so that derived classes don't duplicate it in their
private structs.  Also add a get method for connection
for the same reason.
UrfDeviceHybris: pass NULL object_path to register

urf_device_register_device() now takes an object_path
as a paremeter.  As hybris currently doesn't set an
object_path, pass NULL in the call.
UrfDeviceKernel: fix connection/object_path code

Modify code to use the parent class' connection
and object_path attributes.
UrfDeviceOfono: fix connection/object_path code

Modify code to use the parent class' connection
and object_path attributes.
UrfOfonoManager: use urf_device_get_object_path()
Add async support to the DBus block* & flight_mode

Add asynchronous support to the DBus block* and flight_mode
methods.  This allows urfkill to process responses from
ofono and pass thru failures including InProgress and
EmergencyMode.  This support also leverages the new pre-soft
state recently added to UrfConfig.