New article draft for review: Working with source code markup and code examples for RTL scripts

While working on the new version of 
https://w3c.github.io/i18n-drafts/questions/qa-bidi-unicode-controls.en.html 
(PR at 
https://deploy-preview-449--i18n-drafts.netlify.app/questions/qa-bidi-unicode-controls.en) 
we came across a link to 
https://www.w3.org/TR/2014/NOTE-i18n-html-tech-bidi-20140603/#bidisource, 
which talks about problems when working on bidi source code.  That page 
is out of date and no longer used, so i tried to capture the relevant 
information in a new article.

See https://w3c.github.io/i18n-drafts/questions/qa-bidi-source.en.html 
for an initial draft.

Any comments?

ri