Add support for terminals on Windows

[blink1073]

No description provided.

[rgbkrk]

Sweet

[takluyver]

I tend to do defaults for environment variables like os.environ.get('SHELL') or default_shell, because setting an environment variable to the empty string is equivalent by convention to unsetting it.

[blink1073]

I'm going to hold off on this pending support for Python 2.7 on Windows. cf andfoy/pywinpty#75

[takluyver]

Up to you, but I'm happy for it to be a Python-3-only feature. Next year we might be looking at doing Notebook 6.0 and requiring Python 3, in any case.

[blink1073]

Already mostly done: cf jupyter/terminado#50

[blink1073]

Good to go

[blink1073]

Updated to use powershell on Windows if sh is not available, which is what VS Code uses.

[gnestor]

Thanks @blink1073!

[stonebig]

hi, I think I'm hitting this with Jupyterlab-0.30.5 / terminado-0.8.1 / Pywinpty-0.5.1... Could you do a release soon ?

[liuzhousi]

Sorry to bother.. I think I may encounter the same problem now, as I still could not open the terminal in the latest win10 64bit system. Besides, my environment situation lists below: Python3.6.4, jupyter notebook5.7.8, terminado0.8.2, and pywinpty0.5.5. The detailed problem is: Terminals not available (error was DLL load failed: %This is not a valid Win32 Application.