REACH-29 Save workspace into client file system

In the Flood we can save home workspace and custom node workspaces as files. And later we can restore this workspaces from files.
Save: the Dynamo receives a message about saving, saves all workspaces as files and sends them back to the Flood.
Upload: the Dyname receives a file as byte array, saves them as a file, upload this file, sends all needed for restoring the workspace data to the Flood
if getting the items was failed for some reasons we will have empty but not null list