Introducing socket_datasync

a user-friendly way to notify users when their servers are out of sync, e.g.
http://hercules.ws/board/topic/328-intif-guild-data-size-error/
http://hercules.ws/board/topic/315-error-chrif-authok-data-size-mismatch-52224-52228/

Signed-off-by: shennetsind <ind@henn.et>