Show icon above snapshot card to indicate status

This helps with knowing which ones have been accepted, rejected and
which are pending review.
Move snapshot css to snapshot.css.scss

I took a shortcut earlier and put all the css in global.css.scss. It is
time to start organizing this a bit better.
Improve displaying long URLs

The Url#index page was already doing something to take long URLs into
account. I needed something different for the Url#show page so I added
that and unified their class names to make it more obvious what they do.
Improve vertical alignment of URL on Url#index page

The icon next to the URL was not well aligned with the URL.