added error component and coverage for new components

src/app/shared/error/error.component.ts

@@ -0,0 +1,12 @@
+import { Component, Input } from '@angular/core';
+
+@Component({
+  selector: 'ds-error',
+  styleUrls: ['./error.component.scss'],
+  templateUrl: './error.component.html'
+})
+export class ErrorComponent {
+
+  @Input() message = 'Error...';
+
+}