Investigate re-entrant Properties

[samreid]

In phetsims/axon#179 we identified Property instances that are re-entrant. In this context, re-entrant means a change in value of the Property causes (via listeners) another change in the value of the same Property instance.

Re-entry can occur for at least 3 different reasons, which are document here: phetsims/axon#179 (comment)

value=0.9999999999999998, oldValue=1 // epsilon problem
value=-0.4277580409572783, oldValue=-0.5 // large delta problem
value=[Object], oldValue=[Object] // object changed to object problem.  May be same object?

This issue is to search through the Properties with reentrant: true and:

(a) confirm that the Property really requires reentrant: true
(b) identify the reason for the reentry (may be one of the 3 classes above)
(c-i) see if the code can be rewritten so it no longer requires a reentrant Property, or document why the code uses a re-entrant Property
or
(c-ii) document why the code uses a re-entrant Property

Initially assigning to the responsible-dev for this repo, though it is unclear what the priority should be for this issue.

[zepumph]

Discussed in dev meeting, this should be addressed the next time we work in this repo.

[pixelzoom]

See also #321.