Merge branch 'fix-typos'

Fixes typos found by Fred.
added reference to the documentation's github repository, issue tracker and public wiki.
fixed typos in reST syntax for some links
updated readme copyright information
fixed typeo: DefineColor to definecolor
fixed typo in code example

Added a missing brace to the href.
fixed error: Amazon cloudfront corrected to Rackspace
type: missing " in mspace example
Fixed typos in section on accessibility config
updated old version numbers from 2.1 to 2.2
Merge pull request #12 from mathjax/master

Merge master into v2.2-latest