Based on standard practices, we need to have a copyright and license notice at the top of each source file. Removed existing copyrights and updated/added copyright notices for .h, .cpp, .cs, .ps1, and .psm1 files.
Updated module manifests for consistency to have Author = "PowerShell" and Company = "Microsoft Corporation". Removed multiple line breaks.
Separate PR coming to update contribution document for new source files: #6140
Manually reviewed each change.
Fix#6073
The native command receives the arg ".\test 1" as .\test 1" as the last \" is treated as escaping the quotes. Fix is to add an extra backslash to escape the last enclosing quote.
Steve Lee