#2621 Add support for Hibernate 4.2/4.3.

- Updated Hibernate dependency to 4.2
  - Since all interaction with CacheEntry in the 4.1 case is done via
    Reflection, the exact version of the dependency doesn't matter to
    the (newly renamed) Hibernate41CacheEntrySerializer
  - On the other hand, updating the dependency allows the 4.2/4.3
    version of the serializer to use the CacheEntry interface directly
- Created Hibernate42CacheEntrySerializer to serialize CacheEntry
  instances using the interface methods without Reflection
  - StandardCacheEntryImpl instances are still constructed using
    Reflection because the pre-computed constructor is package-private
- Updated Hibernate4CacheEntrySerializerHook to return a different
  serializer depending on whether CacheEntry is a class or interface

As an additional thing, updated HazelcastCacheRegionFactory to implement
the org.hibernate.cache.spi.RegionFactory interface rather than the
deprecated org.hibernate.cache.RegionFactory interface.
- The spi.RegionFactory variant was added in Hibernate 4.0, so, since
  HazelcastCacheRegionFactory is specific to the Hibernate 4 support,
  there is no reason to implement the deprecated interface
#2621 Code cleanup from review feedback.

- Added a constant for the StandardCacheEntryImpl constructor args to
  be consistent with the Hibernate41CacheEntrySerializer
- Added and updated various Javadocs
- Cleaned up code comments and added spaces for consistent style
- Added @since annotations
#2621 Fixed Checkstyle issues.

- Updated IllegalImport suppression for Hibernate41CacheEntrySerializer
  to match the rename
- Removed trailing comment and made Hibernate42CacheEntrySerializer's
  nested CacheEntryWrapper final