Merge pull request #14 from khanspers/master

updates course listing
Merge pull request #15 from khanspers/master

updates style and nav bar
fixes nav bar and footer
fixes divs
minor update
minor
removes course form button section to test
removes duplicated code
changing style
changes span
removes old
removes "how to run a course" section
add another div
moves a closing div
fixes nav bar
adds missing closing divs
removes extra divs
replaces course listing
Delete courses.html
updates netbio dates