remove tools submodule

Author: Yvonne Yip

.gitmodules

@@ -1,5 +1,5 @@
 module.exports = function(karma) {
-  var common = require('./tools/test/karma-common.conf.js');
+  var common = require('../tools/test/karma-common.conf.js');
   karma.set(common.mixin_common_opts(karma, {
     // base path, that will be used to resolve files and exclude
     basePath: '',

karma.conf.js

@@ -31,7 +31,7 @@
   var basePath = src.slice(0, src.indexOf(thisFile));
 
   if (!window.PolymerLoader) {
-    var path = basePath + 'tools/loader/loader.js';
+    var path = basePath + '../tools/loader/loader.js';
     document.write('<script src="' + path + '"></script>');
   }