Hightlight.js bugs (some fixed in dev version)

[eksperimental]

@Sannis has been working on fixing the current 3 issues we have in posted some time ago in highlightjs/highlight.js#730

He has submitted a PR highlightjs/highlight.js#927 (comment)

He has fixed the issue with the regular expression that broke some of our pages (elixir-lang/elixir#3670), but still is working on the one with the string interpolation#{ } and comments inside sigils.

his PR has not been merged yet. If it finally is, Should we considered building it ourselves?
The author of the library has provided instructions highlightjs/highlight.js#730 (comment)

Version 8.8.0 has been released last week, and it will be another 5 weeks until the next one comes out.

[josevalim]

There is no reason to rush IMO. It has been broken for months and we have been fine. A couple weeks won't hurt anyone.