Cleanup without database...

Send /cleanup response to private user chat instead of current chat.

New command parameter to enforce usage in private chats only.

Update readme to state of 0.46.0

Fix #567

fix get command from type 'new_chat_members'

Update README.md

Scheduler patch

Add 'cleanup' command

Rewrite cleanup command and take prefixed database tables into account.

Bot API 3.1

Closes #550

Make Request::encodeFile public, as it's needed to send files, letting users make use of it.

Keep track of methods that need a dummy parameter for some cURL versions to function properly.

Callbacks can be added to be executed when callback queries are called.

Introduce helper commands for all Update Entity types