CredentialManagerSupport.md

Add CredentialManager support

It's seems many people creating their own credential management solution.

It's seems, solutions classified 2 types of approach. and there are pros/cons respectively.

1. Use OS native Windows Credential Manager(by P/Invoke).
2. Persist encrypted credential to file(JSON/XML) under $profile directory.

Please add standard credential management support to PowerShell.

#Example:
#Set credential to CredentialManager(password is encrypted by DPAPI)
Set-Credential -Id "Admin" -UserName "domain/Administrator" -Password "[Password]" -Persist

#Get credential from CredentialManager
$cred = Get-Credential -Id "Admin"

Also, it may be useful, existing cmdlets -Credential parameter accept string, and automatically resolved to credential by using CredentialManager.