Session data from GET gateway/bot

Created by: Neuheit

Summary

This endpoint's response contains useful information for determining how many sessions are left before a client's token gets reset.

It may be an interesting idea to implement this in the library, and use the data to ensure that the client's token doesn't get reset in case something happens (i.e. have a pre-emptive ratelimit that waits until retry-after if the remaining sessions decrement to 0).