Clicking a book changes the nav, clicking a Folder filters the workspace list

Clicking the "Add" button adds a piece of content to the Book/Folder
instead of just to the workspace
Merge branch 'atc' into prototype-context-sidebar
Load MathJax after the rest of the editor has loaded
Added the lastmodified time

This is updated on save instead of on every change
Merge branch 'atc' into modified-time
Merge branch 'atc' into load-mathjax-last
Moved MathJax for the index page as well
Merge branch 'load-mathjax-last' of https://github.com/Connexions/atc into load-mathjax-last
Added dependency to load jQuery before loading the human-dates plugin
Merge branch 'atc' into load-mathjax-last
Switched to using momentjs

Added dynamically updating the relative last modified time
Merge branch 'atc' into prototype-context-sidebar
Merge branch 'atc' into relative-time-momentjs
Merge pull request #23 from dak1/atc

Update Layout to use new Flexbox
Added event logging to console.
Merge pull request #25 from Connexions/event-logging

Added event logging to console.