Spotlights desy crystfel

• Review here
• Edit here

Closes #351 (closed)

Checklist for authors

• Add a link pointing to the review app

Checklist for reviewers

• File size of images is not too large
• Update date_added attribute
• Centres are referenced by official names
• License is named by SPDX identifier if possible
• All links are pointing to the right place
• Code blocks and headlines surrounded by newlines