mmbackend: avoid possible memory leak
gopal: delete process at the end

So we can use gdb for previous steps.
gopalpcssep: delete commented out code
model: callbacks are private
controller: use the closure on Idle.add() calls

Hence, we avoid using global variables.
controller: stupid boolean error
controller: code style fix
gopalpcssep: remove dead code
gopalpcssep: code style fix
controller: fix set_icon_name() usage
controller: add on_call_request() method
gopalpcssep: opal's callbacks are public
gopalpcssep: constructor for property assignation
gopalmanager: add gopal_manager_add_route_entry()
model: add routes for sip <-> pc
gopalpcssep: pass the remote party name

When OnShowIncoming() is called, the token and the remote party name are
extracted from the connection and passed to the signal emit.
model: catch and process ::call-incoming signal
controller: code style fix
controller: process the ::call-incoming signal
README: update to do list