Full initialization for IDP SWF alternative

This fork of CXF-Fediz is intended to provide an alternative to native
CXF-Fediz IDP based on Spring Web Flow (instead of original
implementation based on filters chain).
Subsidiarily it is also intended to provide a starting point for full
federation supporting WS-Federation 'whr' parameter (remote/requestor
IDP realm).
(relates to https://issues.apache.org/jira/browse/FEDIZ-41)