fixed date

date should be '2012', not '2014'
Deleted a pdf file
Some small edits

Deleted a pdf file, and made some small edits to data products files
Added rstudio lecture and some images
some image files in regression
Finished rCharts and added rgl and rMaps
Small changes to the slidify lecture
Update yhat stuff
Added a second shiny lecture and some example apps
Added a second shiny lecture
Merge branch 'master' of github.com:DataScienceSpecialization/courses

* 'master' of github.com:DataScienceSpecialization/courses:
  update
  nojekyll
  update ghpages
  update
  renamed prediction course
  update
Merge pull request #26 from rdpeng/master

Update yhat stuff
update
Re-export PDF slides
Copy with new name
Re-export PDF slides
Re-export PDF slides
Fix graphs in colors lecture
Merge pull request #27 from rdpeng/master

Re-exported PDF lecture slides
Merge pull request #25 from bcaffo/master

Worked on several lectures in the data products directory