Optimize and enhance highlights bar
Optimize and enhance highlights bar

After trying this on this....

https://github.com/leetreveil/musicmetadata/blob/master/dist%2Fmusicmetadata.js
...page, realized i should optimize the bar (I had been lazy so far;).
Whilst I was there I also added the ability to click and drag on the
bar.

Nuclides/github-highlight-selected,Nuclides/github-highlight-selected