This adds a site setting (default off) to optionally show a user's local time and timezone in their user card. For example, I live in Brisbane, and if at 3:30PM my time I were to open a user who lives in California's card I would see 22:30 (PST).
The {{date}} interpolated value was removed from the English translations in #9329 but not from the other translations, causing breakages.
Also adds a , inbetween date and time for reminders using long_no_year for readability.
