ISPN-5029 Make FileLookup backwards compatible with 6.x

Conflicts:
	commons/src/main/java/org/infinispan/commons/util/FileLookup.java
	core/src/test/java/org/infinispan/configuration/ConfigurationUnitTest.java
ISPN-4948 Package the CLI as a self-standing JAR
ISPN-5017 Include the CLI uberjar in the distribution zip