Add contribution and installation guides

[wilsonbb]

Change Description

Adds installation and contribution guides #46

Note that this still does not update the initial landing page, which we can probably update along with the README

• My PR includes a link to the issue that I am addressing

Documentation Change Checklist

• Any updated docstrings use the NumPy docstring format

[github-actions]

Before [3d65f46]	After [376d883]	Ratio	Benchmark (Parameter)
8.70±0.4ms	9.47±1ms	1.09	benchmarks.NestedFrameAddNested.time_run
33.1±1ms	34.0±2ms	1.03	benchmarks.AssignSingleDfToNestedSeries.time_run
8.51±0.2ms	8.77±0.3ms	1.03	benchmarks.NestedFrameQuery.time_run
259M	263M	1.02	benchmarks.AssignSingleDfToNestedSeries.peakmem_run
275M	277M	1.01	benchmarks.ReassignHalfOfNestedSeries.peakmem_run
86M	86.1M	1	benchmarks.NestedFrameAddNested.peakmem_run
88.2M	88.4M	1	benchmarks.NestedFrameQuery.peakmem_run
88.2M	88.4M	1	benchmarks.NestedFrameReduce.peakmem_run
5.52±0.1ms	5.28±0.03ms	0.96	benchmarks.NestedFrameReduce.time_run
63.2±3ms	60.4±2ms	0.96	benchmarks.ReassignHalfOfNestedSeries.time_run

Click here to view all benchmarks.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.55%. Comparing base (d299612) to head (c9455d6).

❗ Current head c9455d6 differs from pull request most recent head 1d37325. Consider uploading reports for the commit 1d37325 to get more accurate results

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #61   +/-   ##
=======================================
  Coverage   97.55%   97.55%           
=======================================
  Files          16       16           
  Lines         818      818           
=======================================
  Hits          798      798           
  Misses         20       20           

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[dougbrn]

Looks good! Just one nit