build: update dependencies

Update dependencies and configure the app for angular material and flex
layout.

Fixes #44

src/app/core/http/api-prefix.interceptor.ts

@@ -2,7 +2,7 @@ import { Injectable } from '@angular/core';
 import { HttpEvent, HttpInterceptor, HttpHandler, HttpRequest } from '@angular/common/http';
 import { Observable } from 'rxjs';
 
-import { environment } from '@env/environment';
+import { environment } from '../../../environments/environment';
 
 /**
  * Prefixes all requests with `environment.serverUrl`.

src/app/core/http/error-handler.interceptor.ts

@@ -3,7 +3,7 @@ import { HttpEvent, HttpInterceptor, HttpHandler, HttpRequest } from '@angular/c
 import { Observable } from 'rxjs';
 import { catchError } from 'rxjs/operators';
 
-import { environment } from '@env/environment';
+import { environment } from '../../../environments/environment';
 import { Logger } from '../logger.service';
 
 const log = new Logger('ErrorHandlerInterceptor');