TinyMCE for projects

Related to Pivotal Tracker story *Mercury Editor for projects description* https://www.pivotaltracker.com/story/show/64507678.

[TinyMCE editor](http://www.tinymce.com/) for project description in new/edit form, using [tinymce-rails gem](https://github.com/spohlenz/tinymce-rails). My solution for initialization under Turbolinks is probably clumsy - feedback appreciated. It also takes away some of the flexibility of TinyMCE configuration and only allows the default layout specified in config/tinymce.yml.

To see it in action: http://websiteone-nga.herokuapp.com/.
@YaroSpace Doesn't `document` refer to the *current* page? 
To experiment, I stuck
```javascript
$(document).on('page:load', alert('Loaded'));
```
in a `<script>` tag at the bottom of app/views/static_pages/show.html.erb. The alert gets triggered when visiting static pages such as 'About Us' or 'Getting Started', but not on user, events, projects etc. pages. I would take that to mean that the handler got bound only to the the *current page's* `page:load` event.