Allow Timeout to receive timedelta

[KalleDK]

Summary

Added so the Timeout can receive timedelta. I would love to expand that to all the calls, but I thought I wanted your take on this first. I also want your feedback on the documentation, as I think this should only be mentioned a few places as not to overload the general user.

Checklist

• I understand that this PR may be closed in case there was no previous discussion. (This doesn't apply to typos!)
• I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• I've updated the documentation accordingly.