build: Replace Codelyzer and TSLint with Angular ESLint

Migrate from the deprecated TSLint to Angluar ESLint. Also fix current
linting issues in the code, in particular:

- Use strict equals operators (=== and !==)
- Remove empty lifecycle methods (mostly ngOnInit)
- Output bindings including aliases should not be named as standard dom
  events (submit)
- Async pipe results should not be negated

src/app/clients/client-stepper/client-preview-step/client-preview-step.component.ts

@@ -19,7 +19,7 @@ export class ClientPreviewStepComponent {
   @Input() client: any;
 
   /** Form submission event */
-  @Output() submit = new EventEmitter();
+  @Output() submitEvent = new EventEmitter();
 
   constructor() { }