private Properties createLonerConfig() {
    Properties config = new Properties();
    config.setProperty(MCAST_PORT, "0");
    config.setProperty(LOCATORS, "");
    return config;
  }
Tests that configuring a distributed system with a cache-xml-file of "" does not initialize a
cache.

Verifies: "Allow the cache-xml-file specification to be an empty string"

@since GemFire 4.0
geode-core/src/distributedTest/java/org/apache/geode/distributed/DistributedSystemDUnitTest.java