Make v1 clients prompt user to upgrade to v2

minclientversion.php

@@ -0,0 +1,11 @@
+<?php
+
+/*
+ * Give the minimum allowed game client version.  The client should check on
+ * startup and not continue if its version is less than the given version.
+ */
+
+header('Content-Type: application/json');
+header("Access-Control-Allow-Origin: *");
+
+echo json_encode(["status" => "OK", "version" => "2.0.0"]);