ISPN-2924 Update JDK8 backported concurrent classes

* Added revision numbers for each class so that they can be compared
with the CVS repository and see if any update happened since last
time they were updated.
ISPN-2281 Add a CHMv8 that calculates equals/hashCode with function
ISPN-2281 Added Comparing functions to Bounded CHM and XML/prog config

* Comparing function classes for key/values can now be defined via
XML or programmatic configurations.
* If any Comparing functions given, either ComparingCHMv8 or
BoundedCHM taking Comparing function(s) are used.
ISPN-2281 Hot Rod uses byte[] as raw key type instead of ByteArrayKey

* Added EquivalentHashSet and EquivalentHashMap collections to support
byte[] key types in invocation contexts.
* Refactored ConcurrentMapFactory to a CollectionFactory that can
create not only concurrent maps, but maps and sets, based on
equivalence configuration.
ISPN-2281 Hot Rod uses raw values with Cache taking versions

* AdvancedCache adds a couple of new methods that take metadata
as parameter. This can be used by users to provide version, and
also for server implementations to add their own metadata (i.e.
REST servers and MIME data).
* The implementation of these methods is temporary and is bound
to change in order to feed the metadata object all the way to
the cache entry.
* There's an initial stab at the compatibility testing with
initial focus on Embedded and Hot Rod server. Tests here are not
yet working.
ISPN-2281 Implement Hot Rod and Embedded compatibility
ISPN-2281 Leave only EquivalentCHMv8 and make Equivalence Serializable

* Remove CHMv8 and leave only the equivalent version
* Add putIfAbsent with Metadata so that Memcached tests pass
* Add javadocs for Metadata related additions
* Update configuration XSD and remove commented code
* Make Equivalence extend Serializable and fix tests
* Remove commented code sections
* Add missing javadocs