Sensor tool icons should reflow centered layout when others are made invisible

[matthew-blackman]

If a sensor tool icon is removed via PhET-iO, the rest of the sensors should reflow so that they are center-aligned. This applied both within the sensor toolbox as well as the subset of ammeter types.

This issue was discovered in #917

[matthew-blackman]

Things are looking good in the sensor toolbox tree and ready for @arouinfar to review. Note that @samreid and I are aware of a panel alignment issue (see screenshot below) that is exposed by removing tool nodes, but is unrelated to this issue. I will open a separate issue for this.

[arouinfar]

@matthew-blackman looks good! Seems like the AccordionBox alignment hasn't been moved to its own issue yet, so I'll leave this one open so we don't forget.

[matthew-blackman]

Moved remaining panel layout issues to #940

[matthew-blackman]

While working on the featured overrides, @arouinfar and I noticed that the nonContactAmmeterToolNode does not have a visible property. It should have the same tree structure as the voltmeterToolNodes and seriesAmmeterToolNodes

[samreid]

I added that, and it seems to work well in testing. Closing.

[arouinfar]

Looks like there's a regression and this is no longer fixed, as discovered in #987.

[matthew-blackman]

The above commit appears to fix the issue for both DC and DC-VL. @arouinfar please confirm that all combos of voltmeter/ammeters visibility reflow correctly. @samreid if you can code review 2ff682b I think we should be able to MR this into CCK common.

[matthew-blackman]

Commit 2ff682b causes a resurgence of #925.

@samreid @arouinfar and I agree that #925 should be a priority here, since it can appear during student interaction with sim. At this time, we are not going to put more effort into this layout issue. Closing.