Merge pull request #2767 from gschlager/i18n_fix04

FIX: Some default group names could not be translated
Merge pull request #2761 from techAPJ/patch-2

FEATURE: hide google search on 404 page for private instance
minor copy tweaks
FIX: revert readonly on share link field
Correct starred education copy, unclosed ul tag
UX: suppress outgoing right arrow on gutter links
Merge pull request #2770 from techAPJ/patch-1

Correct starred education copy, unclosed ul tag
FIX: better error handling in vBulletin importer
Add classes to the FAQ, Terms of Service, and Privacy nav links so they can be individually styled
FEATURE: Can create warnings for users via PM
Revert "FEATURE: Can create warnings for users via PM"

This reverts commit b0bfc1f93f18b19143a59eafd6d8d2e84a872dcc.
Revert "Revert "FEATURE: Can create warnings for users via PM""

This reverts commit 1c7559380c145136726028ae9f2aeea6f351eb78.
FIX: Only show warning creation to staff. Server side was OK.
FEATURE: add count of previous flags on the post
FIX: remove curvy arrow on reply to topic button
FEATURE: add glyphs in the composer 'save' button
remove border from "reply as new topic"
FEATURE: List moderator warnings on admin dashboard
FEATURE: fix consistency of users.last_posted_at in importers
FIX: Don't break out of remap action if there is a DB error. Display it
and continue.