Add list of Local controllers in group manager(leader) API
Static placement policy on GL
add some tests
add tests for external scheduler support, 
improve external scheduler support :  
* split in virtualclustersubmissionworker looks first to invalid_host_id
* add external scheduler support at GM level
checkstyle fixs
change lookup method in GL
Resize.
ExternalSender = RabbitMQ
Support external monitoring in the config file.

M
Merge branch 'master' into testing

Conflicts:
	src/main/java/org/inria/myriads/snoozenode/groupmanager/virtualclustermanager/worker/VirtualClusterSubmissionWorker.java
	src/test/java/org/inria/myriads/snoozenode/database/api/impl/TestGroupLeaderMemoryRepository.java
Merge branch 'SeveralSender-RabbitMQ' into testing

Conflicts:
	configs/framework/log4j.xml
	pom.xml
	src/main/java/org/inria/myriads/snoozenode/groupmanager/monitoring/producer/GroupManagerSummaryProducer.java
fix
fix genericity issue : 
host/username/passwd/vhost for rabbitmq external data sender.
fix
fix
fix
introduce number of retries and retry interval for external monitoring
Merge branch 'master' into testing
external sender
external sender in repository

M
vm start event