instances - Check instances

Checks all instances or the references for all instances referenced in the source.

When no source is defined, all instances in the database (when GUID check is requested) or the reference collections for all instances (for index and inverse reference check) are checked. When an extent is passed (e.g. Person), all instances stored in the extent are checked (for GUID check) or the reference collections for all instances are checked (for index and inverse reference check). When a path is passed (e.g. Persons().accounts), all account instances (GUID check) or all reference collections for all account instances (index and inverse reference check) are checked.