Add a scale to the optical axis

[pixelzoom]

3/3/2022 for #328

@kathy-phet suggested that adding an optional scale to the optical axis might address some of the measurement issues that @ariel-phet raised in #334.

Notes:

• add an additional checkbox, or show when labels are shown, or use the "Values" checkbox proposed in Show values for important quantities #334, or something else?
• tick marks and values might be the same as the major tick marks on the ruler
• tick marks and values would need to update to match zoom level and browser window width

We decided not to do this for release #278, deferred for consideration in a future release.

[kathy-phet]

Again continue to defer this for now. It does seem like it is still a viable issue for the measurement tool challenge. But let's stay focused on releasing what we have as PhET-iO, and wait for user driven requests.

[pixelzoom]

Agreed. We should not address this for #278, the 1.3 PhET-iO release.