It'd be nice if the default_client was configurable... like:

```
def default_client():
  client_name = get_config.get("hive", "default-client", "cli")
  if client_name == 'cli':
     return HiveCommandClient()
  elif client_name == 'thrift':
     return HiveThriftClient()
  raise Exception("Unknown client type: " + client_name)
```