Sort SSH keys by label (BB-10658)

I have a relatively large number of SSH keys. It would be nice to have the UI for 'SSH keys' display the keys in alphabetical order by key name. This makes it easier to scan the list.

Another alternative the keeps the current behavior is to make the 'Key' and 'Added' column headers sort the SSH keys by that column. So clicking on 'Key' would sort by the key name. Clicking the same header again would sort in reverse order. I've done this for another project where JavaScript does the sorting. If you like I can attach the code to this issue.

It might also be nice to have a find (filter) box for SSH keys, similar to the find box that exists for repositories on the dashboard. This also makes it easy to scan the list, since it is shorter.

If I had to choose just one these three, I'd go for sorting by key name.