Add expando feature

[Magador]

As of today, Angular Material team does not plan to implement the expando feature in the library. However, it is predicted that this feature will be requested for this theme thorough its use across SeedStack projects.

Material Design Guidelines: https://material.google.com/components/lists-controls.html#h.j6uu2bqlxj43-3
Implementation of the Angular Material website expandable list: https://github.com/angular/material/blob/ec2726e067d0851b8e7037f0f75a1fd09610da34/docs/app/js/app.js#L483