Rectify slider and controls names

[samreid]

phetsims/tandem#267 revealed that there are places where a NumberControl is being instantiated but called a Slider. I renamed the tandem, but the class hierarchies should be renamed to update it as well. I'll add 2 TODOS showing the entry points for the problems.

[marlitas]

Re-assigning to myself for the new character set publication.

[marlitas]

@samreid The TODO's you highlighted are actually sliders. This is what the documentation in PhysicalSlider.ts says:

This is just a slider with a label and labeled tick marks. It extends
NumberControl to leverage the layout of the label and slider so that it conveniently matches the layout
with other NumberControls used in this sim.

I think the tandems should be renamed to use "slider" instead of numberControl to match the implementation strategy. At the least, the classes should not be renamed, since they clearly describe what is actually being used and displayed for the sim. What are your thoughts here?

[samreid]

PhysicalSlider extends PhysicalNumberControl which extends NumberControl. So it is more of a "has a" slider rather than "is a" slider, since it doesn't extend HSlider, VSlider or Slider. That's why the tandemNameSuffix: 'Control', was in play. I'm not sure what's best. I'm not really sure why the sim wants to use NumberControl to create a slider instead of just creating a slider. Not sure how much time you want to spend here.

[marlitas]

@samreid and I talked and we decided that things are fine as-is. We are closing this issue.

[phet-dev]

Reopening because there is a TODO marked for this issue.

[Luisav1]

Removed the unnecessary TODO left over. Closing.

[phet-dev]

Reopening because there is a TODO marked for this issue.

[Luisav1]

Sorry, missed removing a TODO referencing this issue. Closing.