[gatsby-remark-embed-snippet] embend only part of files

[ghost]

Summary

It would be nice to embed only part of files delimited by line numbers.

Basic example

I think this should be done in the markdown source, for example an object with key lines. For example to embed line 3 and 12 to 15.

embed:sample-javascript-file.js{lines: [3, 12-15]}

+ add keyword highlight to highlight line directly from markdown. for example: embed:sample-javascript-file.js{lines: [3, 12-15], highlight: [3, 14-15}

Motivation

It would permit to analyse parts of code one by one on a big file.

[m-allanson]

@benjaminabel You're in luck! There's a PR to add this functionality over at #6084. I think it's ready to merge so should be released in the next day or two.

[ghost]

Thanks @m-allanson I didn't find this PR before I opened this issue.