added groupby examples
a Project Starter notebook for OpenContext.org
Merge branch 'master' of github.com:rdhyee/working-open-data-2014
Day 10 and updates
Day 11 -- hint to how to do entropy calculation
Merge branch 'master' of github.com:rdhyee/working-open-data-2014

* 'master' of github.com:rdhyee/working-open-data-2014:
  Day 11 -- hint to how to do entropy calculation
  Day 10 and updates
  a Project Starter notebook for OpenContext.org
  added groupby examples