CacheConfig does not extend MutableConfiguration anymore
cache.getConfiguration now returns an immutable instance, as stated in the spec
listenerConfigurations should be thread-safe now
added null check for waiting count-down completion of sync listeners
added null check in equals
checkstyle
removed sync block since there is no specific rule in spec to check before adding to the listeners set
added np check to near-cache config
Merge branch 'jcache-fixes/master' of github.com:gurbuzali/hazelcast
Removed unused field