feat: Added missing codetag files

plugins/ckeditor4/codeTag/README.md

+Code tag in CKEditor
+==============
+
+![](http://imgur.com/LN0MAEZ.png)
+
+Install by placing in ckeditor/plugins/ and add the following to ckeditor/config.js
+    
+    config.extraPlugins = 'codeTag';
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plugins/ckeditor4/codeTag/plugin.js

+CKEDITOR.plugins.add( 'codeTag', {
+  icons: 'code',
+  init: function( editor ) {
+    editor.addCommand( 'wrapCode', {
+      exec: function( editor ) {
+        editor.insertHtml( '<code>' + editor.getSelection().getSelectedText() + '</code>' );
+      }
+    });
+    editor.ui.addButton( 'Code', {
+      label: 'Wrap code',
+      command: 'wrapCode',
+      toolbar: 'insert'
+    });
+  }
+});
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