Show users times and dates in their time zones

[thestrabusiness]

Is your feature request related to a problem? Please describe.
Currently, all dates and times displayed to users are in UTC. Users should be able to set their timezone and all dates and times should be displayed to the user in the timezone that they select

Describe the solution you'd like

The users table should get a new timezone column, defaulting to UTC. There should be a place in the application for a user to select their timezone. Alternatively, we can update the column via the browser's timezone.

All places where we display dates and times to the user should be updated with the current_user timezone

Another approach would be to avoid a column altogether and just update the timezone on a per-request basis based only on the browser time zone.