add Brand class and associated unit tests

client/src/app/models/brand/brand.spec.ts

@@ -0,0 +1,7 @@
+import { Brand } from './brand';
+
+describe('Brand', () => {
+  it('should create an instance', () => {
+    expect(new Brand()).toBeTruthy();
+  });
+});

client/src/app/models/brand/brand.ts

@@ -0,0 +1,3 @@
+export class Brand {
+  name: string = '';
+}