Switching legends to upper right (what best used to mean)

[joshua-cogliati-inl]

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Pull Request Description

What issue does this change request address?

idaholab/raven#1972

What are the significant changes in functionality due to this change request?

Matplotlib no longer allows 'best' as the legend location. This switches it to 'upper right' (which is what it meant in previous versions)
Update the xml reader to use new methods.
Sort sets before comparing them so it finds the same ones.

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For Change Control Board: Change Request Review

The following review must be completed by an authorized member of the Change Control Board.

• 1. Review all computer code.
• 2. If any changes occur to the input syntax, there must be an accompanying change to the user manual.
• 3. Make sure the Python code and commenting standards are respected (camelBack, etc.) - See on the wiki for details.
• 4. Regression tests have to complete successfully.
• 5. If significant functionality is added, there must be tests added to check this. Tests should cover all possible options. Multiple short tests are preferred over one large test.
• 6. The merge request must reference an issue. If the issue is closed, the issue close checklist shall be done.

[wangcj05]

changes look good.

[wangcj05]

checklist is good, and tests are green. PR can be merged.

[wangcj05]

@joshua-cogliati-inl Thanks for your contribution. I have merged your PR.