Add custom auto-update urls

[netsuileo]

Add telegram proxy auto-update URLs to config and use them in auto-update. This solves the problem of banned core.telegram.org.

Proxy (for example, nginx with simple proxy_pass) for official auto-update URLs may be set up on the server where core.telegram.org is available and used in mtg to get updates.

Other solution would be to make mtg get list of updates via socks5 proxies. If this looks like more reliable solution -- I am ready to contribute and solve the problem of banned core.telegram.org this way.

[9seconds]

Usecase is clear, right, but I'm not aware about any other custom server with such data. Also, right now all communication with Telegram is done using proxy if they are set up. It includes both DC connectivity and http requests to core.telegram.org if it matters. So, we are already quite good here.

Btw, at this moment I recommend to disable auto-update setting. Yes, Telegram can distribute custom DC203 IPs there but they work way less reliable than hardcoded one

[netsuileo]

Alright, thanks for clarification. I'll turn off auto-update for now then.

It seemed to me that requests to core.telegram.org do not use proxies -- that's why I've made this workaround. I've seen errors about blocked requests to core.telegram.org in logs even with added socks5 proxies (although, this proxies work perfectly for main functionality of mtg).

Still, if auto-update feature does not make proxy work better and makes it work worse -- there is not much point in creating workarounds to use it anyways.