Page selector migrated content

[Felwick]

Brief bug description

When page contains a couple of fields with Page selectors - all these fields
will contain all selected documents after migration.

Repro steps

Actual result after migration:
Field [Sliders] contains all published documents under HompageContent > Sliders, HompageContent > Product Catrgories, HompageContent > Logotypes
Field [Categories] contains all published documents under HompageContent > Sliders, HompageContent > Product Catrgories, HompageContent > Logotypes
Field [Logotypes] contains all published documents under HompageContent > Sliders, HompageContent > Product Catrgories, HompageContent > Logotypes

Same steps and details as in issue 185

Expected behavior

Field [Sliders] contains all published documents under HompageContent > Sliders
Field [Categories] contains all published documents under HompageContent > Product Catrgories
Field [Logotypes] contains all published documents under HompageContent > Logotypes