update tools

[githubsands]

solves #19

[CLAassistant]

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[codecov]

Codecov Report

Merging #21 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #21   +/-   ##
=======================================
  Coverage   47.16%   47.16%           
=======================================
  Files           4        4           
  Lines         106      106           
=======================================
  Hits           50       50           
  Misses         55       55           
  Partials        1        1

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