fix #1954 . Start updating API tests, beginning with challenges. Use
test to fix "challenge updates not updating users' tasks"
tests: api.mocha.coffee cleanup WIP
apiv2 swagger fixes to paypal, and send admin emails
challenges: allow members to override challenge.tasks.notes, and sycning
challenge won't update those notes.
challenges: don't disable notes field when challenge-task
challenges: add "official habitrpg challenge" option
challenges: don't remove To-Dos that are part of a challenge when
clearing completed
challenges: but provide default notes
Fix AuthCtrl tests with proper asserts