Versioning of UI and grpc-agent for passing version (#324)

Send Desktop UI client version as user-agent to daemon

This is sent on every login request to the management

Parse the GRPC context on the system package and 
retrieves the user-agent

Management receives the new UIVersion field and 
store in the Peer's system meta

client/internal/engine_test.go

@@ -390,7 +390,7 @@ func createEngine(ctx context.Context, cancel context.CancelFunc, setupKey strin
 		return nil, err
 	}
 
-	info := system.GetInfo()
+	info := system.GetInfo(ctx)
 	resp, err := mgmtClient.Register(*publicKey, setupKey, "", info)
 	if err != nil {
 		return nil, err