Use 5 title buttons on the frontpage

• Add use cases and spotlights to title buttons
• Redefine button size and grid setup
• Add Spotlights and RSD to the software services page
• Rename GitLab service to Software Development Infrastructure
• Link software services page instead of consulting

Review Links

• Front page - 6 Title Buttons
• Software Services Overview

_data/navigation.yml

@@ -21,7 +21,7 @@ header:
       - title: "Identity and Access Management (AAI)"
         url: "https://aai.helmholtz.de/"
         external: True
-      - title: "Software Engineering"
+      - title: "Software Services"
         url: "services/software-overview"
       - title: "Software Engineering Consulting"
         url: "consulting"