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
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 #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
Merge pull request #21 from jaysonvirissimo/patch-4

fixed date
Added some shiny stuff
Merge pull request #30 from bcaffo/master

Added some shiny stuff
Merge branch 'master' of github.com:DataScienceSpecialization/courses

* 'master' of github.com:DataScienceSpecialization/courses:
  Added some shiny stuff
  Fix graphs in colors lecture
  Re-export PDF slides
  Re-export PDF slides
  Copy with new name
  Re-export PDF slides
  update
  Added a second shiny lecture
  Added a second shiny lecture and some example apps
  Small changes to the slidify lecture
  Finished rCharts and added rgl and rMaps
  some image files in regression
  Added rstudio lecture and some images
  Some small edits
  Deleted a pdf file
  fixed date