Support multitouch

[chrisklus]

For phetsims/number-play#4 and phetsims/number-play#5.

I figured out and fixed what I hope is the last way to achieve a mismatch of values on the Ten and Twenty screen when using just a single input method, like a mouse. As the sim continued to fail fuzz testing after this fix, I realized there are a bunch of multi-touch cases that are not being handled correctly. I was able to reproduce several of these on my phone to confirm.

For now, I'm adding guards in key places relating to the Object and Ones that won't fix the multi-touch cases, but they'll keep the current number from going above or below its given range. Hopefully the sim does better on CT with these additions.

In order to (properly) pass fuzz testing, this sim will need to support all multitouch cases. I don't think that's currently a priority, which is why I'm adding the guards mentioned above. I marked them with TODOs that link to this issue.

[chrisklus]

@ariel-phet can you confirm the new screens are higher priority than multitouch, or comment if otherwise?

[ariel-phet]

Yes, new screens definitely higher priority than multitouch

[pixelzoom]

Deferred, will not be addressed in next publication.

[chrisklus]

Also noting that I think this is pretty well supported as is. There hasn't been extensive testing yet, so this issue is not ready to close, but definitely in a far more usable state than when it was created.

[chrisklus]

In the above commit I removed number-play and number-compare from multitouch fuzzing so these sims stop lighting up CT while not under development.

• When multitouch is fixed and supported, add them back in for multitouch testing in listContinuousTests.js