Update to BOT API 5.2

[mircoianese]

The commit 9bbaac4 addresses this issue:

After one of the upcoming Bot API updates, user identifiers will become bigger than 2^31 - 1 and it will be no longer possible to store them in a signed 32-bit integer type. User identifiers will have up to 52 significant bits, so a 64-bit integer or double-precision float type would still be safe for storing them. Please make sure that your code can correctly handle such user identifiers.

Note: I did not run any test on these updates, so please have a look into these before merging.

[pengrad]

thanks a lot!