Relevant BUGIDs:

Relevant BUGIDs:

Purpose of commit: new feature

Commit summary:
---------------
        * modules/pam_namespace/pam_namespace.c: New module
        originally written by Janak Desai.
        * modules/pam_namespace/Makefile.am: New.
        * modules/pam_namespace/README: New.
        * modules/pam_namespace/md5.c: New.
        * modules/pam_namespace/md5.h: New.
        * modules/pam_namespace/namespace.conf: New.
        * modules/pam_namespace/namespace.conf.5: New.
        * modules/pam_namespace/namespace.conf.5.xml: New.
        * modules/pam_namespace/namespace.init: New.
        * modules/pam_namespace/pam_namespace.8: New.
        * modules/pam_namespace/pam_namespace.8.xml: New.
        * modules/Makefile.am: Added pam_namespace.
        * configure.in: Added pam_namespace, test for unshare
        library call.