Try with older rubies

[etagwerker]

This is just an idea suggested by @bronzdoc. Does skunk work with Ruby >= 2.0 and < 2.5?

[etagwerker]

@bronzdoc It seems that supporting Ruby 2.4 or below is not trivial. For example: https://travis-ci.org/github/fastruby/skunk/jobs/671368358

[codecov]

Codecov Report

Merging #39 into master will increase coverage by 0.12%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master      #39      +/-   ##
==========================================
+ Coverage   81.81%   81.93%   +0.12%     
==========================================
  Files          19       19              
  Lines         297      299       +2     
==========================================
+ Hits          243      245       +2     
  Misses         54       54              

Impacted Files	Coverage Δ
lib/skunk.rb	100.00% <ø> (ø)
lib/skunk/cli/commands/compare.rb	86.36% <100.00%> (ø)
lib/skunk/cli/commands/status_reporter.rb	97.67% <100.00%> (+0.11%)	⬆️
lib/skunk/rubycritic/analysed_module.rb	100.00% <100.00%> (ø)
...ib/skunk/rubycritic/analysed_modules_collection.rb	87.50% <100.00%> (ø)
test/lib/skunk/cli/commands/compare_test.rb	100.00% <100.00%> (ø)
...est/lib/skunk/cli/commands/status_reporter_test.rb	100.00% <100.00%> (ø)
test/lib/skunk/rubycritic/analysed_module_test.rb	100.00% <100.00%> (ø)

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[bronzdoc]

@etagwerker it seems that rubycritic is droping support for ruby 2.3 and below, so we probably should do the same.

For ruby 2.4 there is a bug in sexp_processor 4.14.0 that is fixed in 4.14.1