trigger features

[owmo-dev]

The script creating the art should trigger the image capture - via the connector script - rather than wait a certain amount of time.

• Add a small buffer from when "image capture" is initiated to when the next artwork is triggered
• Add an emitter that says "frame is done" so script with variable time to completion can be more efficient
• Continue to allow entering a millisecond timing as an option (toggle between MS and Event, MS by default)