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[chingor13]

• Use a common codecov.sh script that can fetch the codecov api token for this repo.
• Adds badge to README

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@a6585ae). Click here to learn what that means.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #201   +/-   ##
=========================================
  Coverage          ?   75.84%           
  Complexity        ?      313           
=========================================
  Files             ?       20           
  Lines             ?     1354           
  Branches          ?      148           
=========================================
  Hits              ?     1027           
  Misses            ?      254           
  Partials          ?       73

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