directory added
minor
intro change
Update intro.md
update
Merge branch 'master' of https://github.com/datadave/GADS9-NYC-Spring2014 into python_and_data_lesson
Merge branch 'master' of https://github.com/datadave/GADS9-NYC-Spring2014 into python_and_data_lesson
Merge branch 'python_and_data_lesson' of https://github.com/datadave/GADS9-NYC-Spring2014 into python_and_data_lesson
Lesson 3 and 4 Skeleton
Update README.md
Minor edits
Merge branch 'master' of https://github.com/datadave/GADS9-NYC-Spring2014 into python_and_data_lesson