private boolean shouldDeploy(ModuleDescriptor moduleDescriptor,
			ModuleDeploymentRequestsPath path,
			Set<String> previouslyDeployed) {
		return (path.getModuleSequence().equals("0")
				|| !previouslyDeployed.contains(path.getModuleInstanceAsString()));
	}
Evaluate the {@link org.springframework.xd.module.ModuleDescriptor} to
determine if it should be deployed. It should be deployed if:
<ul>
    <li>It contains a module sequence of 0; this indicates it should
        be deployed to every container that otherwise matches its criteria</li>
    <li>The module was not previously deployed to another container</li>
</ul>

@param moduleDescriptor    module to be evaluated
@param path                path for module deployment request
@param previouslyDeployed  set of modules that have already been
                           allocated to a container, the string
                           format is specified by
                           {@link ModuleDeploymentRequestsPath#getModuleInstanceAsString()}
@return true if this module descriptor should be deployed
spring-xd-dirt/src/main/java/org/springframework/xd/dirt/server/admin/deployment/zk/ContainerMatchingModuleRedeployer.java