Yelp/mrjob — pull request #947 by paiweilai1984 (2014-09-26 17:19:48+00:00)
Title: Paiwei infra 2229

Adding a subcommand 'collect-emr-active-stats' to mrjob for counting active emr clusters/instances and print the stats

Active jobflows are those in states of BOOTSTRAPPING, RUNNING, WAITING, and STARTING

Output stats including:
- timestamp: datetime.utcnow().isoformat()
- num_jobflows: computed by adding all jobflows in active states
- total_instance_count: summing all instance counts of active jobflows