Fixed code value in sonata_type_model_autocomplete_widget so it works with embedded admins
Fixed $property name in HelperController::retrieveAutocompleteItemsAction() (was $prop)
- minor change to exception message so apostrophe is not needed
- removed unused Controller reference from top of HelperController
Use sonata_admin.admin.uniqid instead of sonata_admin.admin.root.uniqid
Merge pull request #2303 from caponica/autocomplete_embed_fix

Fix to enable autocomplete in embedded Admins