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/mode/http/http.js

@@ -1,3 +1,16 @@
+// 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"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+"use strict";
+
 CodeMirror.defineMode("http", function() {
   function failFirstLine(stream, state) {
     stream.skipToEnd();
@@ -96,3 +109,5 @@ CodeMirror.defineMode("http", function() {
 });
 
 CodeMirror.defineMIME("message/http", "http");
+
+});