feat: add app shell (angular-material)

Add app shell built using angular-material and flex-layout. Refractor
code due to configuration changes.

Fixes #52

src/app/home/quote.service.ts

@@ -1,5 +1,6 @@
 import { Injectable } from '@angular/core';
 import { HttpClient } from '@angular/common/http';
+
 import { Observable, of } from 'rxjs';
 import { map, catchError } from 'rxjs/operators';