Add hero details, routes, params

[brunolm]

npx ng g c heroes/hero-details

to pass parameters to the router link

[routerLink]="[ '/heroes', hero.id ]"

to add a class if the route is active

routerLinkActive="active"

to get values from params

this.route.paramMap.pipe(map((params) => +params.get('id'))).subscribe((id) => {
  this.activeHero = this.heroes.find((hero) => hero.id === id);
});

Added the package ngx-take-until-destroy to unsubscribe observables.
https://github.com/NetanelBasal/ngx-take-until-destroy

[coveralls]

Coverage increased (+1.6%) to 90.066% when pulling 9c0e7dc on feature/hero-details into 0684e5f on master.