code: func sysCredDelete(cred *Credential, typ sysCRED_TYPE) error {
  	targetNamePtr, _ := syscall.UTF16PtrFromString(cred.TargetName)
  	ret, _, err := procCredDelete.Call(
  		uintptr(unsafe.Pointer(targetNamePtr)),
  		uintptr(typ),
  		0,
  	)
  	if ret == 0 {
  		return err
  	}
  
  	return nil
  }
docs: // http://msdn.microsoft.com/en-us/library/windows/desktop/aa374787(v=vs.85).aspx