Add pagination

[openscript]

Add pagination to the index pages, so not all records are loaded at the same time. Loading all records at the same time leads to increased loading times, especially for the questionnaires index:

Tasks to take care of:

• Decide for the type of pagination: Paging or infinity scrolling
• Implement pagination for questionnaires
• Make sure filters still work
• Implement pagination for all other index pages (carers, languages, studies, participants)