Updated models

src/app/formulaManager/component.ts

@@ -1,8 +1,8 @@
 import {DocumentReference} from 'angularfire2/firestore';
 
 export interface Component {
-  cost: number;
-  created: Date;
+  price: number;
+  createdOn: Date;
   description: string;
   id: string;
   name: string;

src/app/formulaManager/formula.ts

@@ -3,8 +3,9 @@ import {DocumentReference} from 'angularfire2/firestore';
 
 export interface Formula {
   approved: boolean;
+  approvedOn: Date;
   components: {component: Component; quantity: number}[];
-  created: Date;
+  createdOn: Date;
   id: string;
   name: string;
   ref: DocumentReference;