docs(api/rendering): instruction to disable nunjucks

[curbengh]

Mainly to show example usage of hexo.render.renderer.get() method.
This also can be mentioned in this section #1532.

• https://github.com/think-in-universe/hexo-stop-tag-plugins/blob/5494a7f7a0820f61673cb06258743c7caa181c0d/lib/overrider.js#L20-L23

Check List

Please read and check followings before submitting a PR.

• I want to publish my theme on Hexo official website.
  • I have read the theme publishing doc.
  • name is unique.
  • link URL is correct.
  • preview URL is correct.
  • preview URL web site is rendered correctly.
  • Add a screenshot to source/themes/screenshots.
  • Screenshot filename is same as value of name.
  • Screenshot size is 800 * 500.
  • Screenshot file format is png.
• I want to publish my plugin on Hexo official website.
  • I have read the plugin publishing doc.
  • name is unique.
  • link URL is correct.
• Others (Update, fix, translation, etc...)
  • Languages:
  • en English
  • ko Korean
  • pt-br Brazilian Portuguese
  • ru Russian
  • th Thai
  • zh-cn simplified Chinese
  • zh-tw traditional Chinese

[SukkaW]

It is possible that the renderer plugin itself can disable the nunjucks. We could add examples for that as well.

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P.S. We should add needed disableNunjucks for all official hexo plugins (like hexo-renderer-less, hexo-renderer-styl)

[curbengh]

We could add examples for that as well.

+1, but I'm not familiar with the syntax though.

Edit: added example.

We should add disableNunjucks for all hexo plugins.

Obviously except for template renderer (for anyone else reading this). I can add it and learn the syntax.