Updated codemirror to v4.12.

Did a lot of cleanup to limit the size of the plugin.
I kept the emmet plugin.

applications/admin/static/codemirror/addon/lint/javascript-lint.js

@@ -1,3 +1,6 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: http://codemirror.net/LICENSE
+
 (function(mod) {
   if (typeof exports == "object" && typeof module == "object") // CommonJS
     mod(require("../../lib/codemirror"));
@@ -19,6 +22,7 @@
                  "Unclosed string", "Stopping, unable to continue" ];
 
   function validator(text, options) {
+    if (!window.JSHINT) return [];
     JSHINT(text, options);
     var errors = JSHINT.data().errors, result = [];
     if (errors) parseErrors(errors, result);