create chapter abstraction
add test for creating chapters with same name
make chapters actually work
add section starter code
abstract around "an object that is tied to a directory"
rm unused chapter execption type
rm this whole idea of "groups"
update docs to match project
Merge branch 'chapters' for group-abstraction replacement

* chapters:
  update docs to match project
  rm this whole idea of "groups"
  rm unused chapter execption type
  abstract around "an object that is tied to a directory"
  add section starter code
  make chapters actually work
  add test for creating chapters with same name
  create chapter abstraction