Local First Run Results in AttributeError Exception

Hello when starting to test this out, I was immediately faced with the issue below.

Done.

data found from 2018-03-25 14:14:30 to 2018-03-26 05:49:05
Converting to milliseconds ...
Done
Adding time offset of 0.06 seconds
Setting speed to 1x
Done
Traceback (most recent call last):
  File ".../tryingdsio/dsio-env/bin/dsio", line 9, in <module>
    load_entry_point('dsio==0.1.0', 'console_scripts', 'dsio')()
  File ".../tryingdsio/dsio-env/src/dsio/dsio/main.py", line 155, in main
    cols=int(args.cols)
  File ".../tryingdsio/dsio-env/src/dsio/dsio/main.py", line 70, in restream_dataframe
    port=bokeh_port, update_queue=update_queue
  File ".../tryingdsio/dsio-env/src/dsio/dsio/dashboard/bokeh.py", line 74, in generate_dashboard
    if io_loop._running: # Assume we're in a Jupyter notebook
AttributeError: 'AsyncIOMainLoop' object has no attribute '_running'```

I'm not sure what the root cause of the issue is, but I have a non-breaking fix for myself that may also help other people. I will make a PR with the change.

Thank you!

[ffahri]

https://github.com/MentatInnovations/datastream.io/issues/28#issuecomment-401280534 @robmarkcole @amkrous

[robmarkcole]

+1 having this issue