Switch to WebRTC for audio/video calls

[AlexKurisu]

As you may probably know, Telegram nowadays uses WebRTC for calls, so please consider switching to WebRTC for calls

[ars3niy]

Problem is, I don't have any way of testing it at the moment.. The way I made the current voice call support was by finding a bot that calls you, but that one uses libtgvoip's protocol. Another way would be to get a second account and a client that uses the new protocol but I don't have a second phone number.

[mrkiko]

I might help if you want, by helping or providing a phone number you might use! BTW - libtgvoip sends lots of interesting messages, but they completely distrupts the interface while calling from Finch (text frontend to libpurple).