Ticket timestamps should display relative to server time

[noahadler]

Time stamps in the UI use relative times, e.g. '2 hours ago', but relative to the system clock, which is not necessarily in the same timezone as the server which generates the timestamps.

So if someone's clock is set incorrectly or is in a different timezone than the server, the 'relative to now' strings will all be incorrect. E.g., for a user in a timezone an hour behind the server's timezone, a just-submitted ticket will display as '1 hour from now' instead of 'just now'.