Manage display of welcome page

...tweet-wrapper/welcome-tweeter-wrapper.presentational.scss

...nents/routables/welcome-index/welcome-index.routable.html

...nents/routables/welcome-index/welcome-index.routable.scss

...ts/routables/welcome-index/welcome-index.routable.spec.ts

...ponents/routables/welcome-index/welcome-index.routable.ts

src/app/features/welcome/stores/welcome.action.ts

src/app/features/welcome/stores/welcome.state.ts

src/app/features/welcome/welcome-routing.module.ts

src/app/features/welcome/welcome.module.ts

...tationals/shared-search/shared-search.presentational.html

...entationals/shared-search/shared-search.presentational.ts

src/app/shared/enums/local-state.enum.ts

src/app/shared/enums/routes.enum.ts

src/app/shared/models/local-state.model.ts

src/app/shared/stores/language/language.state.ts

src/app/shared/stores/license/license.state.ts

src/app/shared/stores/person/person.state.ts

...d/stores/preservation-policy/preservation-policy.state.ts

...hared/stores/submission-policy/submission-policy.state.ts

src/assets/i18n/de.json