Tracking issue for 3.0.0 release

[JennToo]

I don't know when we'll do this exactly, but this issue will be for tracking things that need to be done whenever we do the next major rev release:

• [x] Remove the deprecated timeout parameters from the connect_* functions
• [x] Ratchet python requirement up to 3.8 (or whatever the oldest non-EOL Python release is at the time)