Break large reports into multiple files

[chrisallenlane]

HTML reports for large projects can grow to be quite large, and thus their in-browser performance can begin to suffer beyond a certain point. To resolve this problem, @antisnatchor recommended splitting large HTML reports out into multiple files. I think this is an excellent suggestion.

In my mind, the best way to do this will be to have the HTML mode output a local site rather than a single HTML file. The site shall be locally linked (ie, not absolutely pathed, for obvious reasons) in much the way that wget will produce when mirroring a site (using common settings).

It is probably most rational to break this site up either on a per-filetype basis (exclusively), or perhaps even on a per-filetype and per payload-group basis. Experimentation will likely reveal the amount of segregation that's necessary.

This change will likely require a change in the way that HTML 5 localstorage is implemented, but that's fine. Some of that code could use a refactoring anyway. This time, I would also like to explore using backbone.js for some of the object-to-DOM mapping.