Minor code and style fixes (#5398)

* type fixes

* import fixes

* fix typos

* fix warning for private props that init in ctor only

* typing fixes

* typing fixes

* style cleanup

* fix test template

lib/core/models/comment.model.ts

@@ -15,11 +15,13 @@
  * limitations under the License.
  */
 
+import { Person } from '@alfresco/js-api';
+
 export class CommentModel {
     id: number;
     message: string;
     created: Date;
-    createdBy: any;
+    createdBy: Person;
     isSelected: boolean;
 
     constructor(obj?: any) {