Added special categories to _config
Add special categories check to index
Made header links programmatic off _config.  also Forkme key off of baseurl
Made howtos folder
Add instructor howtos
Adds include file for Asciicasts
Add how-tos page
corrected asciicasting post
Merge pull request #119 from silshack/howto

Howtos, Asciicasting, and programmatic header