Track Preview Marker

I got some feedback the other day that the 30 second track preview on Dubolt was a little confusing with its previous placement in the album artwork for the track. Likewise, 30 second previews aren't guaranteed on Spotify, so it was not inherently clear which tracks had previews, and which didn't prior to hovering over the tracks.

So, now, tracks that do have a 30 second preview have a 30s marker that appears next to the track name. When you hover over or it, or tap on it on a mobile device, the preview starts, a circular progress bar denotes the percentage completion, and the number counts backwards to denote the amount of time left in the preview.