Announcement: improvements to example-sim

[cmalley]

example-sim is an example simulation created by PhET, see https://github.com/phetsims/example-sim. It demonstrates many of the patterns that are typical of PhET simulations, and is intended to be a resource for developers who are getting started with PhET simulation development.  Feedback in this Group indicated that example-sim was lacking in some respects, so after consulting with the PhET team, I made the following improvements:

* Added a new "Particles" screen, which demonstrates the use of model-view transforms, animation, Emitter, and console logging.

* Improved code comments throughout, to make them more instructional/verbose.

Are these improvements helpful? Do you have ideas for other improvements? Let us know here.

Thanks!

Chris Malley

PixelZoom, Inc.