Backlog: Parse comments for links

It's pretty much expected that URLs will
be auto-linked by any modern app, so there
it is -- in the comments anyway.
Backlog: Comments: Use 'pre' whitespace

Whitespace can be helpful, like with making
lists and whatnot.
Backlog: Comments: Adjust line height

In order to adjust the line height of the comments,
and get the layout we're looking for, we're hacking
up the parse-url directive introduced a moment
ago, so we can make the comment a block element.