User request: 1mm tick marks on ruler

[oliver-phet]

The cm rulers in the following lab are not correct. Centimeter rulers are usually shown as having 10 - 1 mm divisions. The rulers given have 5 - 2mm divisions. This is confusing to students who are used to measuring on standard cm rulers. Please fix if possible. Thank you.

@ariel-phet wrote "I believe that would be an easy change (I am pretty sure that rulerNode supports pretty customizable tick marks). I would be fine with making them be increments of 1mm. I imagine not much thought was put into this design, it was mainly just copying the original flash simulation.

[arouinfar]

Given how large the rulers are in this sim, I think 0.1 cm divisions would be preferable.

@jonathanolson does RulerNode support this?

[arouinfar]

Unassigning myself until work resumes on this sim.