Change to se.kodsnack as package name for app.
Use cool font in bottom fragment.
Add number of listeners to UI. Closes #2.

Had to make some minor refactoring in the callback interface to
facilitate this. This change will also make it easier to show more info
in the UI in the future.
Fix centering issue for multiline status TextView.
Show buffering status in the UI.

Not entirely happy with the UX of this but I'm too tired to think of
something better.