Start lecture on using the R profiler
Merge branch 'master' into profiler

* master:
  added mathNotation lecture
  typos
  Fix paths to images
  Revise paths to libraries/assets
  Move loading/installing packages to new dev directory
  Copy over old CSS file to preserve look
  Libraries directory from dev slidify
  Start the process of creating new directories for using dev version of slidify
  added markdown lecture
  toolBox almost done
  started on data science toolbox
  Added toolbox lecture, hopefully just to jeff
Put lecture on profiler in dev directory
Convert R Profiler lecture from powerpoint
A little more explanation
Merge pull request #16 from rdpeng/profiler

Profiler