Add webpages (admin) => done

...stance/dataset/components/instance-buttons.component.html

client/src/app/admin/instance/instance-routing.module.ts

client/src/app/admin/instance/webpage/components/index.ts

...n/instance/webpage/components/webpage-card.component.html

...n/instance/webpage/components/webpage-card.component.scss

...min/instance/webpage/components/webpage-card.component.ts

...n/instance/webpage/components/webpage-form.component.html

...min/instance/webpage/components/webpage-form.component.ts

...n/instance/webpage/containers/edit-webpage.component.html

...min/instance/webpage/containers/edit-webpage.component.ts

...in/instance/webpage/containers/new-webpage.component.html

...dmin/instance/webpage/containers/new-webpage.component.ts

...n/instance/webpage/containers/webpage-list.component.html

...n/instance/webpage/containers/webpage-list.component.scss

...min/instance/webpage/containers/webpage-list.component.ts

.../src/app/admin/instance/webpage/webpage-routing.module.ts

client/src/app/admin/instance/webpage/webpage.module.ts

...ance/webpages/components/webpage-list-menu.component.html

...stance/webpages/components/webpage-list-menu.component.ts

client/src/app/metamodel/effects/webpage.effects.ts