Adding pkg.go.dev badge and documentation link

[lucasreed]

also fixing trailing whitespace in CONTRIBUTING doc

[codecov]

Codecov Report

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The diff coverage is n/a.

@@           Coverage Diff            @@
##             master     #12   +/-   ##
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  Coverage          ?   0.00%           
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  Files             ?       7           
  Lines             ?     265           
  Branches          ?       0           
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  Hits              ?       0           
  Misses            ?     265           
  Partials          ?       0           

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