studio - checklists: added in smoothscrolling to in-page links across Studio but used only on checklists currently

Merge branch 'feature/btalbot/studio-checklists' of github.com:MITx/mitx into feature/btalbot/studio-checklists

Conflicts:
	cms/templates/checklists.html

studio - checklists: moved content to yaml file, cleaned up new checklists production view, added in page-level nav, and collapse/expand indicators

Merge branch 'feature/btalbot/studio-checklists' of github.com:MITx/mitx into feature/btalbot/studio-checklists

studio - checklists: revised task completion styles, added in checklist visual progress UI and demo/PoC JS and cleaned up some content/status states

Table order fix (again), changes a single character

add management command to regrade partial-credit problems affected by ge...

hot fix for delete_item. The 'delete_all_versions' is useful in that it ...

Make sure that test-requirements.txt doesn't install versions of libraries that requirements.txt has pinned, and cache pip downloads

Make sure that test-requirements.txt doesn't install versions of libraries that requirements.txt has pinned, and cache pip downloads

hot fix for delete_item. The 'delete_all_versions' is useful in that it is set to true when doing explicit deletes as opposed to 'delete draft'. If delete_all_versions=False, then don't remove the deleted item from the parent children collection

Fix/vik/oe pep8

Add logging to debug strange cohort behavior on prod.

do a bunch of pylint improvements

Feature/jkarni/folditx

Strange behavior:
  - There are 20 cohorts that users should be randomly assigned
    into in HeroesX
  - Almost all, but not all (e.g. ~3300 / 3400) users end up in the
    same group.
  - testing manually locally and on prod in a django shell shows
    nothing wrong