Add PSSA test for camelCase/PascalCase for variables and parameters

[fredleejr]

Details of the problem, bug, or enhancement

Many projects follow camelCase and PascalCase style guidelines and are often missed when reviewing. A custom rule for this would be very helpful. I understand a perfect solution would not be possible, but something to catch the obvious.

Verbose logs showing the problem (if applicable)

Suggested solution to the issue

I am currently working on 2 custom rules for this for our project. It is continuing what was started here:

https://github.com/MathieuBuisson/PowerShell-DevOps/tree/master/CustomPSScriptAnalyzerRules

These would be useful as "opt-in" rules that are potentially not enabled by default.

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[johlju]

I'm all for this, if the custom PSSA rules detect that parameter variable names uses PascalCase (both in the parameter declaration and in the code), and another PSSA rule detect other variables (in local, script and global scope) uses camelCase.