Minor cleanup of network manager and items.
Fixed spec after changes to network item base.
Moved vnet-specific db lookup from network manager to vnet edge handler.
Made generic modules for updating the state of items or properties.
Shortened the method name for adding state updates to queue.
Added a default install_item method.
Added ItemDpUuidMode for uuid items with mode property.
Added default unload_item method to manager.
Cleaned up interface manager updated to use new manager methods.
Update service manager with new manager methods.
Cleaned up route manager to use the new manager methods.
Fixed 'network_id_by_mac' call to use self instead of network manager.
Moved manager modules from 'openflow/event_helper.rb' to 'vnet/manager_module.rb'.
Merge remote branch 'origin/master' into refactor-other-managers
Use ActiveNetworks and ActiveRouteLinks helper modules for route manager.
Merge remote branch 'origin/master' into refactor-other-managers
Remove an unused column
Refactor and add examples
Refactored datapath manager.
Fixed method name for update item exclusive.