Reindented HTML
Added (non-functional) button to reset scores
First attempt at adding score reset functionality

Currently, pressing reset hides the scorecard modal, resets the scores
to zero, then shows the modal again.  This happens irrespective of
whether the scores are already all zero.  To fix this will probably
require moving the page manipulation for the scorecard into Controller,
where it should have been all along.
Scores can be reset regardless of whether they’re already at zero (not worth the effort to change) (closes #25)