Simulator GUI: display time in current region

[martinmaher]

As a user of the simulator GUI I would like to see all time displayed in my timezone and the time should include milliseconds so that the time is displayed consistently within and across all GUI pages and so it is possible to reason about the order of messages and actions when the milliseconds are outputted.

Background:

• Within the activity page the messages timestamps are displayed in UTC and the action timestamps are displayed in current region time.
• Within one second multiple actions can be executed and messages can be sent or received so that it is difficult to reason about what happened in what order without milliseconds.