Bug fixes

New best WissKI-Release with basic IIIF-Support.

Cheers!

- #3018171: BulkDocsFactory should return a new instance of the BulkDocs object every time BulkDocsFactory::get() is called
- #2966785: LinkItemNormalizer breaks importing menu links via default content
- Bug fixes.

- #3016096: Fix WorkspaceDeleteForm for Drupal 8.6.x
- #3016367: Hide the workspace from UI when it's queued for delete

Ability to create any type of sitemap via plugins

The 8.x-3.x release allows not only for customizing the URL generation through UrlGenerator plugins as 2.x does, but also creating multiple custom sitemap types through sitemapGenerator plugins and running all the sitemaps on the same Drupal instance. Now e.g a Google news sitemap can be added to a Drupal instance. This is possible through the new concept of sitemap variants.