Fix typescript to comply with jlab3 reqs

Author: marimeireles

src/editor.ts

@@ -31,6 +31,7 @@ w.mxLoadResources = false;
 /* This is a typing-only import. If you use it directly, the mxgraph content
    will be included in the main JupyterLab js bundle.
 */
+// @ts-ignore
 import * as MXModuleType from './mxgraph/javascript/examples/grapheditor/www/modulated.js';
 
 import {
@@ -257,10 +258,8 @@ namespace Private {
         }
 
         _mxLoading = new PromiseDelegate();
-        _mx = await import(
-            /* webpackChunkName: "mxgraph" */
-            './mxgraph/javascript/examples/grapheditor/www/modulated.js'
-        );
+        // @ts-ignore
+        _mx = await import('./mxgraph/javascript/examples/grapheditor/www/modulated.js');
         _mxLoading.resolve(_mx);
         return _mx;
     }

src/index.ts

@@ -13,7 +13,7 @@
 // limitations under the License.
 
 import {
-  ILayoutRestorer, JupyterLab, JupyterFrontEndPlugin
+  ILayoutRestorer, JupyterFrontEnd, JupyterFrontEndPlugin
 } from '@jupyterlab/application';
 
 import {
@@ -53,20 +53,20 @@ const IDrawioTracker = new Token<IDrawioTracker>('drawio/tracki');
 /**
  * The editor tracker extension.
  */
-const plugin: JupyterFrontEndPlugin<IDrawioTracker> = {
-  activate,
+const extension: JupyterFrontEndPlugin<IDrawioTracker> = {
   id: '@jupyterlab/drawio-extension:plugin',
+  autoStart: true,
   requires: [IFileBrowserFactory, ILayoutRestorer, IMainMenu, ICommandPalette],
   optional: [ILauncher],
   provides: IDrawioTracker,
-  autoStart: true
+  activate
 };
 
-export default plugin;
+export default extension;
 
-function activate(app: JupyterLab,
+function activate(app: JupyterFrontEnd,
                   browserFactory: IFileBrowserFactory,
-                  restorer: ILayoutRestorer, 
+                  restorer: ILayoutRestorer,
                   menu: IMainMenu,
                   palette: ICommandPalette,
                   launcher: ILauncher | null