Adding a few general teaching notes
Moving conclusions of discussion from #140 to the teaching notes
Putting intermediate Python lessons into the build
Merge pull request #381 from gvwilson/building-intermediate-python-lessons

Putting intermediate Python lessons into the build
Merge pull request #377 from gvwilson/updating-novice-instructor-notes

Adding a few general teaching notes for novices.
Merge pull request #379 from gvwilson/options-for-teaching-shell-on-windows

Moving conclusions of discussion from #140 to the teaching notes
Merging other changes to teaching notes