Use Telegram API to hide "Loading..." bar

[e-caste]

When we send a command to the bot by clicking on a button, a "Loading..." bar appears at the top of the client for a few seconds, even when the bot has already completed the action.
We should use the API to tell Telegram the bot has terminated an action so that the bar is hidden correctly.

[lvps]

@e-caste The solution is to edit the message instead of sending a new one apparently, no API seems to exist to just tell the client "it's done"