Add bootstrap

[artlowel]

• include the ng-bootstrap module in the project
• Include the sass version of bootstrap 4 separately if that's required
• Ensure there is a global styles file that affects everything on the page (as opposed to scoped component styles)
  • This should be something that can be used by an institution to tweak or add additional css without having to touch the component styles
• Ensure there is a way for bootstrap's stylesheets and variables to be imported in component styles.