Narayana should be configured to use a volatile store by default

The jbossts-properties.xml configuration file in the core module configures a file store by default, and tests have to call TestCacheManagerFactory.markAsTransactional() (or one of the methods that calls it) to configure a volatile store instead.

Furthermore, the jbossts-properties.xml file is explicitly filtered out of the core tests jar, so other modules can't use it.