PhET-iO design review for 1.3 release

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#178 (add support for dynamic locale) will certainly result in many API changes, and there have been many common-code API changes and additions. So this sim will require a full design review of the PhET-iO API.

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Getting this sim ready for dev testing is a task for June 9-29 iteration, so relabeling this issue accordingly.

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Getting this sim ready for dev testing is a task for June 9-29 iteration ...

Noting that I’ll be unavailable June 23-29. So we’ll need to complete this review in time + change requests by next Thursday, June 22. Sorry I didn’t note this sooner.

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@arouinfar anything else to do here, or can this issue be closed?

[arouinfar]

I generally like to keep these review issues open until I complete examples.md just in case I run into any other issues along the way. Examples.md has been completed, no further issues to report, closing.