UI and logic upgrade

I found this app in the Pebble Store and while it was usable, it wasn't really for my taste, so I made a bunch of structural and visual changes. While I'll definitely use my version on my watch, I'm contemplating that others would find it useful as well, hence this PR.

If you like it, feel free to change the app UUID back in appinfo.json (last 9 digit to 8) and release it to the store.
If not, send a comment and I'll publish it separately :)