Merge pull request #16 in BD/bd-swarm from BD-1844-extract-min-and-max-from-labels to master
* commit '0e41ffa5f0070a58efea487911ba97269500f87f':
remove scale_update
make no scale as the default scale decision
fix pep8 error
clean up code on scale up/down condition
handle scales when consumers is 0 in rabbitmq
adjust replica to range of [scale_min, scale_max]
check services''labels' is not empty
use bd.replicas.max/min in sclaing condition checks and skip scaling if they are equal
