as explained in JCR-2963 the version store needs special attention when
it comes to access control and permissions enforced on the store.
for oak we need to define mechanisms on how to control access to the
version store and provide the possibility to limit access to individual
parts of the version store. some possibilities are already listed in JCR-2963.
additional topics include:
- searching for versioned content
- find and restore versions that have no corresponding versionable node in
the content tree
- ability to prevent access to version store altogether without preventing
access to versions/version histories through JCR version operations