(PUP-2738) Puppet::Util::Windows::User refactor

• Presently logon_user raises an exception or returns the error code returned by CloseHandle. Change this to return true if the method executes without error.
• This also affects the load_profile method and the password_is? method. load_profile previously returned the logon_user return value from the outer block, so now returns true upon success, or will raise an error upon failure