Restrict number of lines that can be added to the number of colors we have
todo
Add jQuery Modal (not using it yet)
Minor changes after trying and abandoning handlebars and dust.

Concluded it just wasn't worth either:

* Loading 40Kb+ of JS to compile templates on the fly, and a
  noticeable slow-down of loading the page, or
* Adding another dependency (Grunt etc) to compile templates before
  committing.

It'd be nice to have HTML templates separate from the JS code,
but it seems too much of a trade-off for this site.