Private message emails now include the history
create thumbnails by defaults

changed "create_thumbnails" default value to `true`
FIX: IE9 regression
Merge pull request #1310 from ZogStriP/patch-1

create thumbnails by defaults
Blocked Emails list in admin
Add a way to view staff action logs in admin
Add index to blocked_emails for last_match_at
Oops, forgot to use i18n in some places