[skip validator]

Now, the zip file is created when running `grunt prep-release`.

[ci skip]

[skip sauce]

Fixes #15105.

  - remarkable has 100% support for [commonmark](http://jgm.github.io/CommonMark/spec.html)
  - [faster](https://github.com/jonschlinkert/remarkable/tree/master/benchmark)
  - easier to monkeypatch. this is a goal of ours, might be useful to you at some point given the custom tokenizing/parsing you're doing for documentation.

Close #14664.

* "grunt-jscs-checker" was renamed to "grunt-jscs"
* update deps