This is definitely better than having linkifiers
reach directly into marked.js, but there is
probably further improvement we can do here
to clean up how these regexes get set.
This introduces a circular dependency between
markdown.js and linkifiers.js, but we will
soon break it in the other direction.
The extracted logic is in linkifier.js.
We have decided to name it linkifier.js instead of realm_linkifier.js
because in future when we will add stream-level linkifiers, we'll
likely want them to be managed by this same file.
Steve Howell
akshatdalton