feature(@embark/cockpit): Add contract state changes to cockpit

Add contract state changes to the cockpit by sending contract state updates via the websocket.

packages/embark/src/lib/modules/contracts_manager/index.js

@@ -212,6 +212,9 @@ class ContractsManager {
         this.events.on('contractsDeployed', () => {
           ws.send(JSON.stringify(this._contractsForApi()), () => undefined);
         });
+        this.events.on('contractsState', () => {
+          ws.send(JSON.stringify(this._contractsForApi()), () => undefined);
+        });
       }
     );