Swarm cluster can be created by specifying any of the scheduler
strategy supported by swarm. The strategy can be specified
while creating cluster template using labels parameter, Ex:-
--labels swarm_strategy=spread
Supported values for swarm_strategy=spread, binpack, random
Change-Id: If471f10a3b1f955638a77d5afe462aebdeb4277c
Implements: blueprint add-support-different-strategy-in-swarmbay