Use iterator() and don't allow to grow the QS cache
Editor msg: handle default opts
Editor: prevent working on obsolete units

Follow-up of #3322, which only prevent working on units from obsolete
stores, not obsolete units from non-obsolete stores.
Editor: fixed reloading
Editor: better way to display obsolete messages
Cleanup: breathe
Cleanup: removed dead code
Cleanup: store paidTaskTypes at the module level

Let's not rely on globals for templates either.
Cleanup: use module, don't rely on globals
ItemDelete: added propTypes
ItemDelete: decoupled help text from users
Admin app: decoupled data types from app init
Change sort by filed for `suggestion` filters

We don't need `submission` to access `suggestion` from `unit`.
Fix overwritten submission filter
Avoid accessing to obsolete items from RQ job process

Fix #3418
Don't update cache for project parents

Project doesn't have parents any more.
Use values_list() or values()

Go around Django QuerySet API bug.
Replace a1bb8dc with more efficient methods.
Reports: (re)fixed bogus comparison

Related to 6c119bf
Add RQ job to calculate stats for the newly added project

Fix #3420
Add `projects`, `unit`, `xhr` paths to the list of disallowed ones