Add CSS Cache-busting String

[maxxcrawford]

When deploying new CSS, we should add a cache-busting string on the end of the CSS link:

<link rel="stylesheet" href="/dist/app.min.css?v=1617991325870">

[groovecoder]

Could do this by concat, minify, then hash the resulting css file and append the hash as url param.

[EMMLynch]

Closing since we've redesigned the site and functionality since this was created. If you feel that this is still needed, please let me know.