Started warmup
Added stresstest

Conflicts:
	hazelcast-client/src/test/java/com/hazelcast/client/mapreduce/ClientMapReduceTest.java
	hazelcast-client/src/test/java/com/hazelcast/client/mapreduce/DistributedMapperClientMapReduceTest.java
	hazelcast/src/test/java/com/hazelcast/cluster/ClusterJoinTest.java
	hazelcast/src/test/java/com/hazelcast/mapreduce/MapReduceTest.java
Fixed compile errors
improved pagingpredicate javadoc
Merge pull request #3381 from eminn/pagingpredicatedocs-maint

improved pagingpredicate javadoc
Note related to Binary protocol added.
comment fixes
Backport: Management center update interval  https://github.com/hazelcast/hazelcast/pull/3390
Merge pull request #3400 from emrahkocaman/maintenance-3.x

Backport: Management center update interval
guard sslengine with a lock to prevent calling wrap and unwrap at the same time
removed hosted management center leftovers and added headerless version of documantation to be used in management center
Merge pull request #3411 from eminn/fix/broken-ssl-protocol-maint

[backport] guard sslengine with a lock to prevent calling wrap and unwrap at the sa...
test fix on ClientMapStoreTest. fixes #3416
Merge pull request #3368 from noctarius/mr-partitiontable-warmup-backport

Mr partitiontable warmup backport
fix for issue #3047 (only comparable objects are supported if there is no comparator)
unit test update for issue #3047
fix for issue #3047 (throws exception in case of non-comparable)
unit test for issue #3047 (throws exception in case of non-comparable)
Fixed graceful shutdown interruption because of unknown partition ownership.
fix npe on different write-behind configuration among nodes