Change hard-wired initial size of "Test results" dialogue to be proportional to viewport dimensions

See https://hummy.tv/forum/threads/sweeper-custom-rules-to-manage-recordings.5138/post-140696

webif/plugin/sweeper/script.js

@@ -952,7 +952,8 @@ $('#b_test,#b_run')
 	}
 
 	$('#testresults').dialog({
-		height: '600', width: '800',
+		/* 'auto' is too small: use a big chunk of the available space */
+		height: $(window).height()*0.8, width: $(window).width()*0.75,
 		draggable: true, resizable: true,
 		autoOpen: true,
 		buttons: {