Update mcschema to new mounter system

src/app/AbstractView.ts

@@ -0,0 +1,18 @@
+import { ModelListener, DataModel } from '@mcschema/core';
+
+export abstract class AbstractView implements ModelListener {
+  model: DataModel
+
+  constructor(model: DataModel) {
+    this.model = model
+    this.model.addListener(this)
+  }
+
+  setModel(model: DataModel) {
+    this.model.removeListener(this)
+    this.model = model
+    this.model.addListener(this)
+  }
+
+  invalidated(model: DataModel): void {}
+}