SynthEventList

Takes a list of synth event objects with relative times and schedules them.

properties:

events: Array The event values should be simple JavaScript objects:

{
  defName: 'synthDefName',
  args: {
    out: 0,
    freq: 440
  },
  time: 0.3
}

    Where time is seconds relative to the epoch. The epoch is the start time of
  the dryadic tree, unless a parent Dryad has set a new epoch into context.

 epoch: number|Date|undefined
     Optional epoch that the event times in the list are relative to.
     Can also be updated by the updateStream
     default: context.epoch or now

updateStream: Bacon stream to push updated event lists of the form: .events Array .epoch number|Date

  Pushing a new event list cancels previous events (not yet implemented)
  and schedules new events.

  Note that by default the epoch will be unchanged: relative times
  are still relative to when the Dryad tree started playing or when any parent
  Dryad set an epoch in context. This means you update the currently playing score
  but it doesn't restart from the beginning, it keeps playing.

    Optionally you may push an .epoch with the updateStream. This can be a date or timestamp
  slightly in the future. If you pass "now" then any events at 0.0 will be too late to play.

defaultParams: a fixed object into which the event value is merged.