CI with GitHub Actions

[leferrad]

This PR is intended to change CI process from Travis to Github Actions

[codecov]

Codecov Report

Merging #12 (d8ebd51) into master (4dfb2a2) will decrease coverage by 12.98%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           master      #12       +/-   ##
===========================================
- Coverage   93.75%   80.76%   -12.99%     
===========================================
  Files           2        1        -1     
  Lines          48       52        +4     
===========================================
- Hits           45       42        -3     
- Misses          3       10        +7     

Impacted Files	Coverage Δ
src/tesseract.jl	80.76% <0.00%> (-12.85%)	⬇️
src/OCReract.jl

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