ROENROLL-1796 basic DARS NGRX stuff and metadata observables

src/app/dars/audit/audit.component.html

src/app/dars/audit/audit.component.ts

src/app/dars/dars-view/dars-view.component.html

src/app/dars/dars-view/dars-view.component.scss

src/app/dars/dars-view/dars-view.component.ts

src/app/dars/dars.module.ts

src/app/dars/metadata-table/metadata-table.component.html

src/app/dars/metadata-table/metadata-table.component.scss

src/app/dars/metadata-table/metadata-table.component.ts

src/app/dars/store/actions.ts

src/app/dars/store/effects.ts

src/app/dars/store/reducer.ts

src/app/dars/store/selectors.ts

src/app/dars/store/state.ts