Getting rid of downvoted material
Markdown version of spatial intro
Merge pull request #386 from gvwilson/adding-markdown-for-spatial-intro

Markdown version of spatial intro
* replaced msysgit with Git for Windows

msysgit != Git for Windows
1.  Cutting "How Learning Works" material from index to instructors' guide.
2.  Putting link to instructors' guide on site home page.
Adding notes to teaching guide
Merge branch 'master' into removing-unwanted-novice-extra-material
Incorporating @amyrbrown's edits to novice extra material
Incorporating @amyrbrown's edits to extra material on code review
Incorporating @amyrbrown's edits to man page description
Updating with @amyrbrown's edits
Adding link to explainshell.com
Incorporating @amyrbrown's copy editing
Incorporating @amyrbrown's copy editing
Incorporating @amyrbrown's copy editing
Incorporating @amyrbrown's copy editing
Incorporating @amyrbrown's copy editing
Adding Markdown class to div's
Cleaning up novice extras
Merge pull request #391 from gvwilson/removing-unwanted-novice-extra-material

Updating novice extra material.