Angular src restructured as modular as per angular official guidelines, .travis.yml support added for node 12

src/app/shared/directives/webview/webview.directive.spec.ts

@@ -0,0 +1,8 @@
+import { WebviewDirective } from './webview.directive';
+
+describe('WebviewDirective', () => {
+  it('should create an instance', () => {
+    const directive = new WebviewDirective();
+    expect(directive).toBeTruthy();
+  });
+});