Support to specify parser plugins

[chinesedfan]

Fixes #228 and solved #183 in another way.

Now users can use options.parserPlugins to custom plugins to babel.

[coveralls]

Coverage remained the same at 100.0% when pulling d27a9e3 on parser-options into 3ca7c63 on master.

[rylek90]

Is there an option not to rewrite whole array but rather concatenate with default one?
Can we work towards passing whole Babel configuration in the future?

[chinesedfan]

@rylek90 See #231. Please feel free to send a PR if you would like do that.

[rylek90]

@chinesedfan thanks, I will take a look at it if I'll have some free time 🙌

[jeffcatania]

Is there any documentation on how to use this option?

[chinesedfan]

@jeffcatania I am afraid not because #231 should be the better way. You can use the test file(options.test.js#L211) as a Node API example now. Following links may
also help you.

• How to config processor options: https://stylelint.io/user-guide/configuration/#processors
• Available babel parser plugins: https://babeljs.io/docs/en/babel-parser#plugins