important resolvers for the file management view

Move the functions of OlatRootFile and OlatRootFolder to the Local
implementations to simplify the use of VFS, implements factory methods
in VFSManager, reduce the number of call to meta informations in folder
listing

Fix deletion of metadata, fix left files by restore of versioned files,
implement restore of metadata of deleted versioned files, implements an
upgrader to delete metadata of deleted resources, courses, groups,
forums, users and temporary uploaded files

of administrator role in organisation tree, enhance UI in user
management and fix some permission issues to edit invitee and guest,
remove admin by-pass for the full text search...

organization, implement segment view for user visit card to better
inline in user management, implements several features for all roles
(allow enrollment, mandatory confirmation email by enrollment, allow
autocomplete, bulk changes...), add roles like lecture manager, quality
manager..., enhance the roles editor in user management

OO-3297: refactor the user management to use organization for managing the roles instead of named security groups

OO-2975: delete imported calendar after course, group and user deletion, implement a check every 10 runs to remove deprecated imported calendar, append the job to the scheduler