Feature: Upgrade to angular 8.1.3

[merolhack]

Related issues

Fixes: #20

Changes proposed in this pull request

• Upgrade the angular versions to 8.1.3
• Bugfix in the file, missing asterisk in package name added:
  • /src/app/pages/pages/login/login.component.ts

- import { AuthService } from '@services/';
+ import { AuthService } from '@services/*';

• Linting warnings removed
• Charts refactored due an errors in the console
• Bugfix in the upgrade of the core-js in the src/polyfills.ts file.

The imports have changed for core-js version 3.0.1 - for example
import 'core-js/es6/array'; and import 'core-js/es7/array';
can now be provided simply by the following
import 'core-js/es/array';

Source: https://stackoverflow.com/a/56186570/1006079