Hanging indent for long lines

[hcayless]

In order to get "proper" formatting for long lines in the HTML, that is, wrapping like:

This is a very long line that goes on past the container width
     and wraps around.

I think we would need to wrap lines in an element, such as a <span class="line">, which could then have the appropriate CSS applied to it. This is probably doable either as a post-processing step in the XSLT or using JavaScript running on the page (the latter might mean a visible reformatting of the text just after loading, so it might be better to do it in the XSLT).