Simulator locking - Need to check browser clock accuracy

[rpeach-sag]

We seem to have an issue where computer clocks are not synchronised....

Solution:

• get the time from the server
• compare to the local time
• store the offset
• add the offset to the local time before we send any times to the server
• Periodically update the offset (every 5mins?)

Potential issues with solution:

• The offset also contains the latency from the initial server call
• Hopefully this isn't too much of an issue because every user's offset will have a similar latency included (hopefully similar latencies, never anywhere near 5 seconds)

[rpeach-sag]

I suspect that this was actually the issue: #24