Allow services to exist only in later versions

- createService() was raising an exception of a service was not found in the
  currently selected version of the API. However, this is normal; a service may
  be added in a later version, and thus not available in version 1 or other
  later versions. Modified createService() to return false in such situations,
  and other code checks for that boolean false value before performing
  operations with the return value.