Fix html

Add a missing closing tag to the HTML, and correct indentation.
Add required form

The assignment states:

	The website must include a form with a variety of appropriate
	input elements designed to gather information relevant to your
	website's purpose. The data will be submitted to the php echo page
	we used for the forms assignment, but you should design the form
	as if it were intended to do real data collection and processing.

So, this commit adds a form which submits the winner of the game and
the number of pieces the winner has left to the echo page.