.window is how many of the latest polls we examine.
.threshold is how many must have succeeded for the backend to be healthy.

	.window = 40;
	.threshold = 30;
		// Thirty of the last fourty polls must have succeed.

	.threshold = 4;
		// The last four polls must have succeeded.

Default values:
	.window = 8;
	.threshold = 3;



git-svn-id: http://www.varnish-cache.org/svn/trunk@3098 d4fa192b-c00b-0410-8231-f00ffab90ce4