WFLY-2057 Fix issue with deployment unit processors being registered with same priority

Conflicts:
	appclient/src/main/java/org/jboss/as/appclient/subsystem/AppClientSubsystemAdd.java
	ee/src/main/java/org/jboss/as/ee/subsystem/EeSubsystemAdd.java
	ejb3/src/main/java/org/jboss/as/ejb3/subsystem/EJB3SubsystemAdd.java
	jpa/core/src/main/java/org/jboss/as/jpa/subsystem/JPASubSystemAdd.java
	jsf/subsystem/src/main/java/org/jboss/as/jsf/subsystem/JSFSubsystemAdd.java
	server/src/main/java/org/jboss/as/server/ServerMessages.java