Fixed issue #1 and some other fixes

src/app/shared/utils/object-keys-pipe.ts

@@ -1,7 +1,15 @@
 import { PipeTransform, Pipe } from '@angular/core';
 
 @Pipe({name: 'dsObjectKeys'})
+/**
+ * Pipe for parsing all keys of an object to an array of key-value pairs
+ */
 export class ObjectKeysPipe implements PipeTransform {
+
+  /**
+   * @param value An object
+   * @returns {any} Array with all keys the input object
+   */
   transform(value, args:string[]): any {
     const keys = [];
     Object.keys(value).forEach((k) => keys.push(k));