Dash description reformat

Nontrivial (as in, larger than a word or two) dashboard descriptions format poorly in the current layout, which just nests a `<small>` within the `<h1>`.

Moving the description to its own `<h2>` looks much better and doesn't appear to sacrifice anything obvious, re: style/layout.

Took opportunity to do a tiny refactor while fixing this :) DRY FTW.