Documentation: Add SonarQube Code Recommendations to Contributor Guide

[jprestop]

Describe the Task

SonarQube provides recommendations for cleaner code and Howard has been implementing these changes. For example:

• Do NOT use parentheses in return statements anymore.
• Minimum scope for local variables. Move local vars as close to their use as possible.
• Use nullptr instead of 0 to initialize pointers.
• Prefer strings to character arrays.

We'd like to maintain a list of advice to be included in the Contributor’s Guide. We should also consider reviewing older SonarQube PRs for other changes already made that are not included in the list above. Additionally, it would be great if we could find these SonarQube recommendations online and link to these recommendations.
See C++ standard version related rule tags, for example.

Time Estimate

<1 day of work

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Relevant Deadlines

None

Funding Source

TBD

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Define Related Issue(s)

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• METplus, MET, METdataio, METviewer, METexpress, METcalcpy, METplotpy

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