ctrl-c does not seem to terminate all studio CLI services

[vince-leaf]

When using CTRL-C on some occasions not all of the threads within the python CLI are shutdown causing the CLI to remain partial running. An additional CTRL-C will remove the remaining threads and terminate the CLI.

2018-11-15 08:26:15 INFO   CompletionService - Studioml completion service shutting down
2018-11-15 08:26:15 INFO   RabbitMQShutdown - Initiating RMQ cleanup for queue rmq_vnguyen_rBranch_LEAF67_integration_textclassifier
2018-11-15 08:26:15 INFO   RabbitMQShutdown - RMQ cleanup started
2018-11-15 08:26:15 INFO   RabbitMQShutdown - RMQ connected
2018-11-15 08:26:15 INFO   RabbitMQShutdown - Bound StudioML.topic to rmq_vnguyen_rBranch_LEAF67_integration_textclassifier with StudioML.rmq_vnguyen_rBranch_LEAF67_integration_textclassifier
2018-11-15 08:26:15 INFO   RabbitMQShutdown - queue rmq_vnguyen_rBranch_LEAF67_integration_textclassifier purged.
2018-11-15 08:26:15 INFO   RabbitMQShutdown - Unbound StudioML.topic from rmq_vnguyen_rBranch_LEAF67_integration_textclassifier with StudioML.rmq_vnguyen_rBranch_LEAF67_integration_textclassifier
2018-11-15 08:26:15 INFO   RabbitMQShutdown - Deleted queue rmq_vnguyen_rBranch_LEAF67_integration_textclassifier
2018-11-15 08:26:15 INFO   RabbitMQShutdown - stopping
2018-11-15 08:26:15 INFO   RabbitMQShutdown - closing the channel
2018-11-15 08:26:15 INFO   RabbitMQShutdown - closing connection
2018-11-15 08:26:15 INFO   RabbitMQShutdown - channel closed 0 
2018-11-15 08:26:15 INFO   RabbitMQShutdown - RMQ stopped
2018-11-15 08:26:16 INFO   MinioShutdown - Initiating minio cleanup for target storage
2018-11-15 08:26:18 INFO   MinioShutdown - Initiating minio cleanup for target database
Shutting down completion service...
Shutdown completion service with following signal: 2