Don't update Queue on initialization

[MikeDacre]

There is actually no need to know what is in the queue until the Queue class is queried, so let's drop the update call from the Queue initialization.

Also, each Job class doesn't really need its own Queue, we could just create a single Queue class and link all Jobs to it.

[petercombs]

One way to go about this would be to have an option in Job.__init__ to take queue as a keyword argument, and otherwise fallback to create its own. i.e.
self.queue = kwds.get('queue', _queue.Queue(user='self', qtype=self.qtype))
(although note that you would need to update the allowable keyword args in options.py.

[MikeDacre]

Yeah, that's a pretty good idea. I could also make the default an instance-wide default loaded at the top of job.py, that would add a potential hang point during the initial import, but would make the default be the already created class.

I wonder if there is a way to add a timeout in python for external commands? That would be really helpful here, as I could then add a timeout for the instance-wide version.

Another option would be to make the instance-wide version a placeholder and populate it only if it does not currently exist.