Add net-im/telegram-cli

Telegram-cli is a command-line interface
for the Telegram instant-messaging network.

WWW: https://github.com/kenorb-contrib/tg

This is a repocopy of net-im/telegram. There are 2 reasons for it:

1. net-im/telegram upstream (https://github.com/vysheng/tg) is not active anymore. Telegram CLI is being maintained by a community gathered around a fork on GitHub: https://github.com/kenorb-contrib/tg. People might want to stick to the original version of Telegram CLI, so let's give them an option to do that.
2. Most other packaging systems package this piece of software as telegram-cli (see https://repology.org/project/telegram-cli/versions). Let's take this opportunity to have a package name consistent with other projects.