ThriftHiveMetaStoreCore is not closing the HiveMetastore when shutdown() is called.

[patduin]

ThriftHiveMetaStore code starts up a HiveMetastore which starts a Hive Thrift server. Hive doesn't provide any hooks to shut it down. So in our tests the started threads keep running even when interrupted. When you're running a junit test this means stuff isn't shutdown until you the actual test finishes. Not entirely sure if this is causing issues for users (we've seen hanging tests but it is difficult to determine if this is causing it). We could experiment with starting the HiveMetastore as Process and kill the process when we are done with it. (similar to starting a metastore on the cli and shutting it down).