Update Telegram icon #51
Description
As stated here, we need to update Telegram icon on our Resources page to this.
We're using some free CDN to download font-awesome now through CSS import. This CDN doesn't provide font-awesome 4.7.0.
Font-awesome recommends to either register on their CDN by email (and I don't want to manage this registration at all) or download their files and serve them from our server. Probably we'll want to go third way: download these resources from npm as part of our frontend build pipeline (note that currently we have no pipeline at all) and incorporate it into our CSS through @import.