Updated html R notes.

Added cophenetic correlation to compare hierarchical clustering and
added several more heat maps with different clusterings of rows and
columns.  Added correspondence analysis and plot of cross table as
another way to show topic relationships.  Made the code a bit more
generic and fixed some typos.
Include .Rmd file and topic .csv data files.

The .Rmd file corresponds to the .html notes file.  The data files were
converted to .csv files externally at the start of the project to be
used for the exploratory data analysis.