Open Stack

Hi, I'd like you to take a look at this patch for potential
DocImpact.
https://review.openstack.org/23820

Log:
commit c9ab14eef5f4aa7005ede0a842ade9a15409d304
Author: Alvaro Lopez Garcia <aloga at ifca.unican.es>
Date:   Wed Mar 6 16:41:46 2013 +0100

    Improve authentication plugins management
    
    The current auth plugin system lacks some functionality to be used with
    other methods that might require additional configuration options or
    that do not require a user to pass some options that are now compulsory
    (for example, X.509 authentication needs to get a certificate file, and
    do not need neither a username nor a password). We implement several
    functions to handle this extra features, while remaining compatible with
    older plugins.
    
    Implements: blueprint authentication-plugins
    DocImpact
    
    Change-Id: I7b0ef4981efba8160dea94bf852dba7e2e4068f5