[DURACOM-240] working directive

need to change markdown pipe to markdown directive and put everything in there

src/app/core/shared/math.service.spec.ts

@@ -0,0 +1,16 @@
+import { TestBed } from '@angular/core/testing';
+
+import { MathService } from './math.service';
+
+describe('MathService', () => {
+  let service: MathService;
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({});
+    service = TestBed.inject(MathService);
+  });
+
+  it('should be created', () => {
+    expect(service).toBeTruthy();
+  });
+});