Docker/Panel fixes and improvements

[luiztauffer]

• fix requirements for Dockerfile
• improve docker/readme
• github action to build and publish Image on new releases
• local mount option, depends on Better local file component #300

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@057cfed). Click here to learn what that means.
The diff coverage is 57.14%.

@@            Coverage Diff            @@
##             master     #299   +/-   ##
=========================================
  Coverage          ?   66.22%           
=========================================
  Files             ?       35           
  Lines             ?     3467           
  Branches          ?        0           
=========================================
  Hits              ?     2296           
  Misses            ?     1171           
  Partials          ?        0           

Flag	Coverage Δ
unittests	66.22% <57.14%> (?)

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Impacted Files	Coverage Δ
nwbwidgets/panel.py	76.96% <53.84%> (ø)
nwbwidgets/version.py	100.00% <100.00%> (ø)

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[bendichter]

lgtm! @CodyCBakerPhD could you take a look as well since you know more about this type of devops stuff?

[CodyCBakerPhD]

Yes, I've been keeping my eye on it and will make some comments later as I notice a couple things while adding similar stuff to catalystneuro/neuroconv#383

[luiztauffer]

@CodyCBakerPhD any specific things you see that should be blocking this merge? I wanted to get the dockerized mode updated and start releasing the images alongside the pypi releases, it will make it very easy to run Panel remotely always with the latest updates