cleaning up
major reorg of notebook names, movement of non-essential directories out of trunk
 more cleanup
rename and remove notebooks in appendix
rename and remove notebooks in appendix step2
fixed some text in intro notebook
additional content in intro
new README
reformatting README
license added
data cleanup worksheets
linear regression data cleanup notebook commit. random forests still being tested, not yet committed
 all work from last three weeks checked in. All known issues fixed. Two new notebooks created.
cleaned up dataset directory and edited DIRECTORIES.md file to make it current
rm-ed redundant notebook
minor cleanup
 renamed DIRECTORIES.md to FILES.md