Streamline user's time zone selection

There could be an faster way to set a user's time zone so you can spend less time scrolling through the list. This might cover both when you're creating a new user, and when you're updating an existing user's time zone (including your own).

Potential approaches might include defaulting to the same time zone as the person creating the new user, defaulting to the computer's local time zone, showing the most commonly used time zones at the top of the list, or making the dropdown list searchable.