(#32) Add PSScriptAnalyzer

[TheCakeIsNaOH]

Description Of Changes

This adds a task to run PSScriptAnalyzer. It utilizes the Cake.Powershell
module to run a script that will get ps1/psm1 files that are not excluded
and run them through the specified settings file.

Either a default formatting only run can be done, or custom run(s) can be
specified. A custom base analysis path, setting file and set of folder
exclusions can be specified for each run. For example, a custom run can
be created to check that the Chocolatey powershell helpers use only the
PSv2 cmdlets.

The default run is for formatting, it checks files against the build in
formatting related rules. This run can be expanded in the future, once
enough projects are up to a baseline of good scripting practices.

Motivation and Context

See #32

Testing

1. Clone this repository locally and checkout this PR branch
2. Copy the contents of the Chocolatey.Cake.Recipe/Content folder to the tools/Chocolatye.Cake.Recipe.0.24.0 folder in the chocolatey/choco repository
3. At the command line for that repository, run the following build.bat. The build should complete successfully, and a new task Run-PSScriptAnalyzer should be completed, which adds two new files into the code_drop\TestResults\PSScriptAnalyzer folder
4. At the command line for that repository, run the following build.bat --shouldRunAnalyze=false. The build should succeed, but all the analyze steps should be skipped, and no files added into the code_drop\TestResults\PSScriptAnalyzer folder
5. 2. At the command line for that repository, run the following build.bat --shouldRunPSScriptAnalyzer=false. The build should succeed, but all the analyze steps should be skipped, and no files added into the code_drop\TestResults\PSScriptAnalyzer folder, but other test results, for example, InspectCode, should be generated.

Change Types Made

• Bug fix (non-breaking change)
• Feature / Enhancement (non-breaking change)
• Breaking change (fix or feature that could cause existing functionality to change)
• PowerShell code changes.

Related Issue

Fixes #32

Change Checklist

• Requires a change to the documentation
• Documentation has been updated
• Tests to cover my changes, have been added
• All new and existing tests passed.
• PowerShell v2 compatibility checked.

[gep13]

NOTE: As a result of running the build using the changes in this PR, two new PowerShell Modules will be installed, PSScriptAnalyzer, and ConvertToSARIF.

[gep13]

@TheCakeIsNaOH would be great to get your thoughts on this PR as well. I have made some changes on top of the work that you originally did here.

Mainly around the installation of the PS Modules, and also switching to use Start-Job as I found that any call to Invoke-ScriptAnalyzer caused the terminal to hang when invoked through Cake, and you had to CTRL+C out of it.

[TheCakeIsNaOH]

Overall the concept looks good, a couple of comments/questions.

[vexx32]

I'm not seeing any additional concerns here beyond what @TheCakeIsNaOH has already raised tbh, this looks pretty good otherwise. :3

[gep13]

LGTM!

[gep13]

@TheCakeIsNaOH thanks again for the start on this work! Really appreciate it!