Fixes #3420 (partial) - Adding PowerShell modules

[dodexahedron]

Initial PR for analyzer work, but this is its own component so makes sense as a standalone PR.

This adds PowerShell modules for use when developing Terminal.Gui. Future enhancements are planned and suggestions are more than welcome.

This PR is ready to go as-is. Analyzer projects will come in another PR, after I rebase and finish shoring a few things up.

Proposed Changes/Todos

• [x] Add powershell modules/scripts to perform routine operations when developing Terminal.Gui.
  • [x] Terminal.Gui.PowerShell module: Environment and solution functionality.
  • [x] Open-Solution: Launches the Terminal.sln file
  • [x] Close-Solution: Closes running devenv.exe processes with Terminal.sln loaded
  • [x] Set-Environment: Sets up a standard environment for script execution, in a temporary session.
  • [x] Reset-Environment: Undoes changes made by Set-Environment or just exits the inner session, if requested.
  • [x] Terminal.Gui.PowerShell.Analyzers module: Functionality related to analyzer projects.
  • [x] Build-Analyzers: Builds analyzer projects in Debug and Release mode, with additional functionality exposed via switch parameters.

Pull Request checklist:

• [x] I've named my PR in the form of "Fixes #issue. Terse description."
• [x] My code follows the style guidelines of Terminal.Gui - if you use Visual Studio, hit CTRL-K-D to automatically reformat your files before committing.
  • Well... It's PowerShell, so it's different, but it's pretty similar.
• [ ] ~My code follows the Terminal.Gui library design guidelines~
• [ ] ~I ran dotnet test before commit~
• [x] I have made corresponding changes to the API documentation (using <# #> style comments)
• [x] My changes generate no new warnings
• [x] I have checked my code and corrected any poor grammar or misspellings
• [x] I conducted basic QA to assure all features are working

3420 should not be closed once this is merged, as the Analyzers are part of that as well.

[dodexahedron]

Whoah, what happened here?

Let me make sure the branch was done correctly... Something ain't right...

[dodexahedron]

Oh whoops. Forgot to target v2_develop for the PR. 🤦‍♂️