POCS.park() doesn't park bisque mount

[AnthonyHorton]

Describe the bug
When calling POCS.park() with Huntsman (which has a bisque type Mount) there is an unhandled TheSkyXTimeout error immediately after sending the command to home the mount, which results in the subsequent mount park command not being sent. Consequently the mount ends up being left at the home position instead of the park position. Seems like POCS is not waiting for the home mount command to complete?

To Reproduce
Steps to reproduce the behavior:

1. Create a POCS instance with an Observatory that has a Mount of bisque type.
2. Start the POCS instance running.
3. Invoke POCS.park().

Expected behaviour
The mount first moves to the home position (why?), then to the park position.

Actual behaviour
Mounts starts moving to the home position, there is a TheSkyXTimeout error, the mount does not park.

[wtgee]

This probably just needs to implement the blocking=True option created in #887. The default was left to False so there wouldn't be any unexpected changes from what currently existed.

Note that the parameter is currently being passed, just need to build in some kind of check and timeout.

https://github.com/panoptes/POCS/blob/develop/pocs/mount/bisque.py#L206-L223

[wtgee]

Related: AstroHuntsman/huntsman-pocs#102

[wtgee]

Not recreating this either. Seems like with #916 and #917 there was something causing that TheSkyXTimeout to occur, which was making each of the commands fail. This was also before we had the odd TSX communication errors. Will leave open for now until we find out more info.