New sample problems and updates

[pstaabp]

Added new Sample problems and updated existing problems.

Updates includes

• removing the subjects of 'answer' and 'graphs' and reclassifying appropriate places for these problems. These two should never have been subjects.
• running perltidy again on the sample problems.
• adding some additional links (categories, see_also, ..)

Note: for the new VectorGraphTool problem, #1195 needs to be merged.

I've also updated the list of sample problems that @drgrice1 posted earlier to
setSample_Problems.def.txt

[Alex-Jordan]

I have merged #1195, and it changed since you opened this PR. I haven't looked but I suspect you may want to revise the sample problem for that tool.

[pstaabp]

Just updated the sample problem for the vector graph tool and added a line segment graph tool problem.

[drgrice1]

There are several changes needed here.

First , please reformat the problems that you added. Always try to fit into an 80 character text width whenever possible. That is what we have the pg perltidy script set to use. One reason for that is that even with a wide browser window anything more will wrap and look bad in the problem editor.

Note that the sample-problems/Geometry/LineSegmentGraphTool.pg problem is not in the set definition file that you posted. I am just noting this so that others testing this pull request will know to add it (or look at it in a different way).

[pstaabp]

I think the couple that I reformatted to be more narrow was just due to a narrow screen I was using in the ProblemEditor. If I use vscode, I get the 80 limit as a vertical line. Do you know if CodeMirror6 has the ability to include a vertical line at a given width. That might be helpful.

I have made updates on these and just pushed.

[drgrice1]

When I asked that the problems be formatted to fit into the 80 character limit, I mean the entire problem. That means documentation and PGML sections as well. That is what I did with the existing sample problems in the last related pull request. I see this still has not been done.

[pstaabp]

I double checked all of the problems.

The only cases that I think remain is when the categories or sample problems list goes beyond, but I think we'd have to rewrite the script to handle that.

[drgrice1]

That is better. Yeah, the categories have to be on the same line at this point.

The next thing to look at is the wording in the documentation of the new problems. For example, in the LineSegmentGraphTool.pg it says

Below we will ask to graph the line segment between these two and add the
correct answer `{ segment, solid, ($sx1, $sy1), ($sx2, $sy2) }` creates this
line segment as a solid line.

First it has the "royal we" I said to try and get rid of. Second, it is a run on sentence.

Then a few lines later in the same documentation it states:

Mulitple line segments can be added to the graph tool, but note that there is
a Triangle Graph Tool, PROBLINK('TriangleGraphTool.pg') and a Quadrilateral
Graph too, PROBLINK('QuadrilateralGraphTool.pg') as well.

Technically that is not a run on sentence, but it is a conjunction between two sentences that are really unrelated, and reads quite poorly.

[pstaabp]

I do use the royal "we" and will look overthing again.

[pstaabp]

Made some more changes. Got rid of the royal "we" and tried to be more consistent with the style of the other problems.