replace LaserNode with scenery-phet.LaserPointerNode

[pixelzoom]

... as recommended in phetsims/models-of-the-hydrogen-atom#2.

When options.hasKnob, you'll need to add the knob as a decoration, as you've done for the prisms that can be rotated (see PrismNode).

Remember to delete related images and assets.

[samreid]

@ariel-phet this issue could be given to another developer if desired--not too much bending-light knowledge required. Can you help prioritize and assign? The main point is to use the new scenery-phet LaserPointerNode @pixelzoom developed for Models of the Hydrogen atom in Bending Light instead of custom raster images.

[ariel-phet]

@samreid since bending light is published, this seems fairly lowly priority, agreed?

[samreid]

Yes, it would not significantly change the user experience, it is mainly an internal maintenance issue.

[ariel-phet]

Ok, going to clear assignee for the moment, will revisit when appropriate. This sim is actually a very good candidate for phet-io work at some point, to see if we can deal with a complicated sim. I am guessing the work could be wrapped into that effort.

[samreid]

Thanks to the changes in the referenced issues, this has been completed. @pixelzoom do you have time for a quick review? If not, we may need to leave this for a "review right before publication" sort of thing.

[pixelzoom]

Changes and behavior in bending-light look good, so I'll go ahead and close this. But note the regression in phetsims/scenery-phet#660 (comment), which does not appear to affect bending-light, since its LaserPointerNode uses the default hasGlass: false.