Use postMessage to communicate between the iframe and TinyMCE.

This gets around cross-origin issues on the CDN.
Tiny MCE version 4.0.20

Changed tiny-MCE to not load CSS files dynamically.
Added CSS files for tiny-MCE in env files.
Moved TinyMCE files to directory structure required by Jake command.
Changed clients of "tinymce.min.js" to use "tinymce.full.min.js" instead.
Directions for creating tinymce.full.min.js and commenting of edX changes.

Updated comments related to disabling dynamic JS and CSS file loading in tinymce.
removing tinymce button border only on active to counteract fun LMS button styles
Add dialog plugin code to compressed JS file and CSS file.

Needed for TinyMCE CodeMirror plugin.
Directions for creating codemirror-compressed.js