lc-esp-eo-engine: Implemented iterable EOAssoc cursor which is AutoCloseable for automatic resource cleanup

lc-esp-eo-engine: Added ctime support to objects & associations

lc-esp-eo-engine: Supported automatic deletion of inverse associations

lc-esp-eo-engine: Improved transaction test case

lc-esp-eo-engine: Good working transaction semantics. Fixed up test case to clean up after itself in the cluster.