after this change any restore_structure_step processor
method is able to instruct the dispatcher about to skip
any path below it. Until now, we were doing the checks on
each child processor method, but that was inneficient and
prone to errors (easy to miss the check in a child so some
orphaned piezes of restore may be causing mess here and there).
Once implemented, it's simlpy a matter of the parent deciding if
all its children must be processed or no. Easier for developers
and also small speed improvement because avoids unnecesary
dispatching/processing to happen.

Surely only will be used in parts of core, like in question_categories,
saving 50-60 sub processors (sub-paths) to be dispatched.