added introduction
Added 'Loading' code chunk and md5 checksum file.
fixing bug due to non working stop() + typos
Updating 'Loading' and 'Preprocessing'
Adding ggplot2 to welcome/setup, small changes to PreProc and adding 1st question.
Updated RStudio version and the way the MD5 hash is checked.

Now the checksum is hardcoded, so the *.MD5 file is not needed.
2nd question
Adding 'figure' folder
3rd question, part I
3rd question, parts II and III

need to find a better solution yet.
4th question
Adding a new plot to histograms. Some plot formating changes. Code reformating for increased readability.
Change download source to public github account
Adding output files (.md and .html)
Update environment: new Kernel
Changed output format
Vectorized (and much faster) implementation of the filling algorithm.
Error in 'opts_knit' if library is not loaded.
typos
Updated 'Welcome' to allow improved reproducibility