Make sure a book is selected
Hide Coach on a new run to avoid confusion
Use the users course on selecting code
add site-packages to include pythonds and test
diffviewer should start at  the end
Add video help section to instructors page
update change log
adding a section to introduce the idea of a main function
remove extraneous console.logs
Add course name to dashboard
need to populate base_course earlier
tidy up the processing when base_course is unknown
added discussion of conditional execution of main via __name__
Merge pull request #483 from ranum/mainfunction

adding a section to introduce the idea of a main function