Replication service

[tshemsedinov]

• In globalstorage load category Replication will be selected to memory cursor and hold all replication objects in memory.
• Replication Destination will connect to Source and subscribe for updates then wait for data (no pulling). Connection should not be duplicated if destination-source pairs repeated with different Category field.
• After connection opened we need to compare Category.Versions to detect, do we need synchronization. Before synchronization finished all incoming events from Source should be queued.