Events that fire at t0 don't work with non-zero start times and delays or the 'time' csymbol

[luciansmith]

When an event fires at the start of a simulation (due to its 'initialValue' being set to 'false', but its trigger evaluating to 'true'), there's a couple issues:

1. if the trigger involves the csymbol 'time', that time is assumed to be zero.
2. if the event has a delay, the delay is calculated and its 'assignTime' (EventQueue.cpp line 46) is calculated from the model's current time, which is zero.

I think we could clear this up with a revamp of 'reset': currently, the EventQueue is set up with the 'reset' from 'load', and subsequent resets (there's another later on with a time of zero before the simulate function gets involved at all) don't clear it. I think we might revamp reset so that it clears and re-sets the event queue with the current simulation start time, then call it from 'simulate', which is the first time we actually know when the initialTime is.