Move OfficeHour Calendar to use UTC

[tehalexf]

Two things have to be done:

1. Load and store in locally PST, server UTC*.
2. Update all rows in db to offset by 8 (Currently in PST, move to UTC), and set the timezone as UTC.

*(Perhaps have server/external resource set the local timezone so that even if the local clock is wrong, it will be correctly set on the server?)