clean up CHUNK_SIZE globals
do not square chunk_size...
avoid extra request per call of UnknownUsersPillow
improve ptop fast reindexer logging
add logging around fast reindexer view requests

and log the dump file names
minor cleanup of ptop_fast_reindexer
add log for sending chunk to ES
condense full_couch_view_iter
do not skip gevent patch thread in ptop_preindex

this change fixes the following behavior:
- ptop_preindex hangs after starting a couple greenlets and never finishes
- you cannot ^C out of it
update staging.yaml

[ci skip]
Merge branch 'ptop-reindex' into autostaging
Merge branch 'historical-forms' into autostaging
Merge branch 'remove-hutch' into autostaging
Merge remote-tracking branch 'origin/subscription-no-contact-info' into autostaging
Merge remote-tracking branch 'origin/revert-4574-revert-4553-case-list-redesign' into autostaging
Merge remote-tracking branch 'origin/revert-4205-revert-3841-86347-2' into autostaging
Merge remote-tracking branch 'origin/masterlist-workflow' into autostaging
Merge remote-tracking branch 'origin/graphing+double-management' into autostaging
Merge remote-tracking branch 'origin/double-management' into autostaging
Merge remote-tracking branch 'origin/bulk-app-translate' into autostaging