Attempt to fix multi value handling with placeholders
This partly reverts and augments 131fd50
The validator call is needed to transform the given value into to proper format (eg. an array for multivalues or an array of array for multi-page values). This has to be done after applying place holders.
This might also fix #729
It might also break other usecase so it needs more real world testing. Overall the bureaucracy handling is a mess, because bureaucracy is a mess. Until splitbrain/dokuwiki-plugin-bureaucracy#303 has been addressed, there is no good way to fix this.
setVal is called on parsing (and then cached) and later again on action submit. We should not validate on parsing as this would destroy placeholders. Placeholder do need to be applied on rendering to keep them dynamic. I pushed a commit trying to address both issues.
@solewniczak could you check if this branch works with your setup?