pinned ansible version to fix #51 (#52)

diff --git a/docker-compose/Makefile b/docker-compose/Makefile
index 25263ab..89d98e2 100644
--- a/docker-compose/Makefile
+++ b/docker-compose/Makefile
@@ -101,7 +101,7 @@
 	rsync -a $(PROJECT_HOME)/* ~/tmp/openwhisk/src --exclude .git --exclude build --exclude tests
 	docker run --rm -v ~/tmp/openwhisk/src:/openwhisk -w /openwhisk/ansible \
 	    --network="host" -t \
-	    williamyeh/ansible:debian8  \
+	    ddragosd/ansible:2.3.1.0-debian8  \
 	        ansible-playbook setup.yml initdb.yml wipe.yml \
 	            -e db_host=$(DOCKER_HOST_IP) -e openwhisk_home=/openwhisk -e db_prefix=$(OPEN_WHISK_DB_PREFIX)
 
diff --git a/docker-compose/docker-whisk-controller.env b/docker-compose/docker-whisk-controller.env
index fe0ab38..eeb351f 100644
--- a/docker-compose/docker-whisk-controller.env
+++ b/docker-compose/docker-whisk-controller.env
@@ -21,6 +21,7 @@
 LIMITS_TRIGGERS_FIRES_PERMINUTE=60000
 LIMITS_ACTIONS_INVOKES_CONCURRENTINSYSTEM=5000
 LIMITS_ACTIONS_SEQUENCE_MAXLENGTH=20
+CONTROLLER_BLACKBOXFRACTION=0.10
 
 LOADBALANCER_ACTIVATIONCOUNTBEFORENEXTINVOKER=10
 LOADBALANCER_INVOKERBUSYTHRESHOLD=16