Add uninstallation instructions for PowerShell pkg
Add uninstallation instructions for PowerShell pkg

JamesWTruher/PowerShell-1,KarolKaczmarek/PowerShell,jsoref/PowerShell,jsoref/PowerShell,JamesWTruher/PowerShell-1,TravisEz13/PowerShell,KarolKaczmarek/PowerShell,bingbing8/PowerShell,bingbing8/PowerShell,PaulHigin/PowerShell,PaulHigin/PowerShell,bingbing8/PowerShell,KarolKaczmarek/PowerShell,bingbing8/PowerShell,JamesWTruher/PowerShell-1,bingbing8/PowerShell,jsoref/PowerShell,TravisEz13/PowerShell,KarolKaczmarek/PowerShell,TravisEz13/PowerShell,daxian-dbw/PowerShell,PaulHigin/PowerShell,daxian-dbw/PowerShell,JamesWTruher/PowerShell-1,PaulHigin/PowerShell,daxian-dbw/PowerShell,KarolKaczmarek/PowerShell,TravisEz13/PowerShell,jsoref/PowerShell,daxian-dbw/PowerShell,jsoref/PowerShell