allow messages to be sent to a telegram broadcast channel

[naspert]

No description provided.

[ableev]

@naspert hi, thanks.
What is the point of the diff?
There is ability to send to a channel as to a private chat.

[naspert]

hello. yes sending works, but when retrieving the id of a private channel, the response was not parsed correctly in get_uid, resulting in 'chat' not being set. This patch allows the retrieval of the id of a private channel. I guess the title of the pull request could be improved :)