Add pry-rails for better development console
Should not cache GuestUser instance

If `current_user` is called before a session, it would cache that user
as a `GuestUser` even if the session later should have logged in the
user.
Adding timezone to users

Different users will need to view in different timezones. While we still
do not have the means for users to change the default of UTC, it will
open the door to helping alleviate timezone issues in our specs.