Standardizing the Federation Process

Split functionality for attribute extraction and mapping layer
for saml2 auth plugin. Renamed to mapped.py, leaving original file
for backwards compatibility.

Co-Authored-By: Guang Yee <guang.yee@hp.com>
Implements: bp generic-mapping-federation

Change-Id: If9a8cbf62334c796a70e939bf00e7b194e5749c8
Merge "Standardizing the Federation Process"