Merge branch 'gh-pages'
Delete the output graphic files from the revtest_MM1990 example data folder
Generate new .zip of Datafiles folder
Add url to cookbook website to README file
Update readme.md 

Update readme.md to explain procedure for regenerating .pdf and .html of the cookbook
Fixed typo in the readme.md file
updated links to Essentials textbook
Merge branch 'master' of https://github.com/ltauxe/PmagPy-Cookbook