Updated/Fixed Docs Layout

This fixes #74.  I added some responsive breakpoints so the docs should look nice on phone, tablet, desktop, and huge screens.  The TOC could be more useful on small devices, but it's the best I can do with pure CSS. You can preview it here: http://aearly.github.io/mori/

Also:

- Modernized the html -- now more semantic and compliant html5
- Fixed some broken links
- Included mori.js from cdnjs.com so you can play around with it in the console
- Minor readability tweaks

It looks good an all the browsers/devices I have on hand.  The only major category I didn't test is mobile/desktop Safari.  It will also likely break on IEs before IE10.