fixes #455
Merge remote-tracking branch 'origin/master'
only apply maximum cache size to guava cach if it is greater than zero
Merge pull request #457 from notz/master

Hazelcast Client NearCache is only working if Maximum Size is defined which is not default
correctly handle non existing map keys in client near cache implementation
added checks for handling non existing map keys in client near cache implementation
Merge pull request #458 from notz/master

Fixed client NearCache handling of non existing map keys
heartbeat timer on client was scheduled with wrong delay causing no heartbeat.
Removed System.out.println() lines.