Adding windows install instructions

[shanaxel42]

I was a little more specific about how to install a pip and a virtualenv since I ran into lots of issues with accidentally overriding apt-get files.

[codecov-io]

Codecov Report

Merging #1227 into master will decrease coverage by 20.89%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1227      +/-   ##
==========================================
- Coverage   88.38%   67.48%   -20.9%     
==========================================
  Files         132      133       +1     
  Lines        4897     5262     +365     
==========================================
- Hits         4328     3551     -777     
- Misses        569     1711    +1142

Impacted Files	Coverage Δ
starfish/experiment/builder/inplace.py	0% <0%> (-87.88%)	⬇️
starfish/test/full_pipelines/api/test_dartfish.py	20% <0%> (-80%)	⬇️
starfish/test/full_pipelines/api/test_iss_api.py	23.52% <0%> (-76.48%)	⬇️
starfish/test/full_pipelines/api/test_merfish.py	24.39% <0%> (-75.61%)	⬇️
starfish/experiment/builder/__init__.py	30.35% <0%> (-69.65%)	⬇️
starfish/intensity_table/overlap.py	31.37% <0%> (-64.71%)	⬇️
.../spots/_detect_spots/local_search_blob_detector.py	30.38% <0%> (-63.69%)	⬇️
starfish/spacetx_format/test_fuzz.py	37.5% <0%> (-62.5%)	⬇️
starfish/spacetx_format/util.py	37.5% <0%> (-58.34%)	⬇️
starfish/util/click/__init__.py	40.74% <0%> (-55.56%)	⬇️
... and 69 more

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[ambrosejcarr]

Can't test this myself, but this looks solid to me.

[ttung]

Lgtm thanks