Change list total to absolute positioning

[mateusnroll]

Since Trello added the ellipsis button to the right, the list total was breaking to the second line.

This makes it absolute positioned and hence fixes the issue – I hope :). It fixes #97. The updated build looks like this:

I went with the absolute positioning because:

1. It will be less likely to break something they introduce. The alternate approach would be to change the .list-header to a flex container, which means messing with Trello's CSS – I guess it's not something I should be doing unless necessary.
2. The ellipsis button is already using absolute positioning, so why not?
3. Changing to a flex container would break the card count, this does not.

I hope this helps 👍