Array utility class for listing pre-known ProviderIDs Typical use of this class is to define a strict list of ProviderIDs pointing to certain IDPs, which are to be accepted as only suitable services when initiating an new service connection.
Other possiblity is to instantiate a non-strict array, which only acts as "recommendation" of those Identity Providers, that should be first checked when initiating new service connection. In such case, because it is a non-strict list, also other IDPs may be used, if none matching with this "recommendation" is found.
