[review] enable and use +CGEV indications

[Aleksander Morgado]

Hey all,

See this MR, that allows us to enable and parse +CGEV indications to
e.g. report context disconnections via URCs.

https://gitlab.freedesktop.org/mobile-broadband/ModemManager/merge_requests/49

My target is to try to disable the periodic connection checks
(AT+CGACT?) for all modems that support these indications, but first
I'd like to integrate this and see how it behaves.

Comments? Suggestions?

-- 
Aleksander
https://aleksander.es