Fixed ERRAI-532: Errai fails to find array marshallers for non-concrete types in DevMode
Merge branch '2.3'

Conflicts:
	errai-marshalling/src/main/java/org/jboss/errai/marshalling/rebind/DefinitionsFactoryImpl.java
	errai-marshalling/src/main/java/org/jboss/errai/marshalling/server/MappingContextSingleton.java