fixes #5140

[czpython]

• Fixed Page marked as "pending" on move even if unpublished #5140
• Fixed bug where an unpublished child page would be set to pending if it's parent was unpublished.
• Refactored move_page to no longer publish pages.
  instead it now calls mark_as_published and mark_descendants_as_published.
  This is to avoid executing the whole publication logic on page move which can result in many
  inconsistencies.
• Refactored the logic from publish() that updates the state of descendant pages
  into a new method called mark_descendants_as_published.
  This is to allow other actions like moving a page to benefit from this operation without
  calling publish(). The refactor removed a lot of dead code.

[coveralls]

Coverage increased (+0.002%) to 88.485% when pulling fe1db22 on czpython:fixes-3.3/5140 into 582b1af on divio:develop.

[czpython]

@yakky @mkoistinen please review.
I will backport this into 3.2.x once merged.
This fixes a few critical issues on 3.2.x and thus a new release there should be planned.

[mkoistinen]

This looks really good, @czpython. Also, thanks for both retaining existing and writing new comments. Very clear code, easy to follow and thorough. 👍