Start to create new lesson 9 further Git
Session 8 notebook changes
Session 9 and stub for 10
Notebook and slides for L9
Advanced git removed from slides
Revert "Rehide future lessons"

This reverts commit 26aceef76370387b591203a5264f7479cae51353.
Merge branch 'staging'

* staging:
  Advanced git removed from slides
  Notebook and slides for L9
  Session 9 and stub for 10
  Session 8 notebook changes
  Start to create new lesson 9 further Git