disable sending email or show presence when forgot system user password
use system user helper and constant when it's referred
FIX: Should be 30 topics on desktop, 15 on android
FIX: Not highlighting posts when entering a topic
FIX: Sharing buttons broke in 1.9 template upgrade
FIX: when private messages are disabled in settings, flag modal shouldn't show private message options
UX: Let's try an animating heart out
Merge pull request #3034 from fantasticfears/filter_system_user

disable sending email or show presence when forgot system user password
Revert "UX: Let's try an animating heart out"

This reverts commit eb445ca2fcfa614ab14eda3bb5503b77748de3b5.