Release notes for 12-18-2013

First draft
Release notes edits

Release notes edits
Typos

Fixed a few typos in Building a course document
Removed number from RN TOC

Removed number from RN TOC
Fixed image

fixed image path
Added alt text to image

accessibility
Merge pull request #2009 from edx/markhoeber/documentation/release-notes-12-17-13

Markhoeber/documentation/release notes 12 17 13