Currently, Pawtograder has one option for time zone support: Courses are placed in a time zone, and all deadlines are shown in that time zone. If a user's browser is set to a different time zone, they get a warning to take notice of this.

We should support configurable time zone support for each user. If a user is not in the course time zone, they should be shown a modal dialog that asks them to choose one of two options:

1. Continue to view the course in the course time zone (NAME_OF_TIME_ZONE), save a cookie that remembers this so that they do not get the modal dialog next time in same browser
2. View the course in the browser's time zone, translating due dates into their current time zone (also saves this preference as a cookie).

Either way, whenever we display a due date, it must be extremely clear what timezone each deadline is in. This will likely require several rounds of iteration to reach an adequate design.

cc @espertus