Metadata: Correct filters to limit to AAF entities group.

References #142.

Previously our AttributeFilter supplied peristentID and transientId
to all AAF SP. This is fine except for IdP which have bilateral
agreements with SP like MS Office 365 which misbehave when supplied
these attributes.

Instead this change now limits supply these default values to AAF
metadata grouped SP only.
Merge pull request #142 from ausaccessfed/feature/#142-limit-attr-filter-aaf-entities

Limit AAF top level filter policies to our groupID to remove impact on bilateral agreements IdP might have.