* fix #https://github.com/hazelcast/hazelcast/issues/325
* some minor improvements for object creation prevent if no logging needed
* some minor code cleanup (extract constant)
fixes #530 a npe in the connectionmanager. Appearently the socketAcceptorThread can be null when stop is called
Merge pull request #531 from pveentjer/fix/2.x/npe-in-connectionmanager

fix #530 a npe in the connectionmanager. Appearently the socketAccepto...
Merge pull request #524 from pveentjer/fix/3.0/SystemLogService-OOME

fix #https://github.com/hazelcast/hazelcast/issues/325