include all valid emails in the mailing list
add mailchimp API
subscribe users to mailchimp on signup
handle changes to emails and email opt outs
fix opt in/out inconsistency
Merge remote-tracking branch 'origin/multimedia-case-properties' into autostaging
Merge remote-tracking branch 'origin/sql-dailyformstats' into autostaging
Merge remote-tracking branch 'origin/pretty-user-display' into autostaging
Merge remote-tracking branch 'origin/cache-locations' into autostaging
Merge remote-tracking branch 'origin/hq-dropdown' into autostaging
Merge branch 'mailchimp2' into autostaging
update submodule refs