modules/ims_usrloc_scscf: add dialog data to contact and tear down dialog when contact is removed
        Added info to contact structure to store active dialogs for contact
        When contact is removed terminate all active dialogs
        Added new API functions: api->add_dialog_data_to_contact and api->remove_dialog_data_from_contact
modules/ims_charging: new capability to add dialog data to contact when charging session is created
	When charging session is created dialog data is added to contact in usrloc (to be removed if contact is removed)
	New exported parameter: single_ro_session_per_dialog allows to call Ro_CCR on term and orig in config file but only 1 charging session is created
modules/ims_charging: updated documentation for new parameter: single_ro_session_per_dialog