eslint: add support for package.json configuration

[43081j]

fixes #316.

adds support for eslintConfig in package.json which is supported by ESLint alongside the usual .eslintrc* files.

[codecov]

Codecov Report

Merging #326 into master will increase coverage by 0.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #326      +/-   ##
==========================================
+ Coverage    98.4%   98.41%   +0.01%     
==========================================
  Files          32       32              
  Lines         563      569       +6     
==========================================
+ Hits          554      560       +6     
  Misses          9        9

Impacted Files	Coverage Δ
src/special/eslint.js	100% <100%> (ø)	⬆️

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[rumpl]

👍

[cyrilchapon]

Is parser: babel-config (at the root of package.json) supported ?

[43081j]

@cyrilchapon as far as i can see, the correct way to specify an eslint parser in your package manifest should be:

{
  "eslintConfig": {
    "parser": "babel-eslint"
  }
}