Add a common module (libcloud.common.xmlrpc) for handling XML-RPC
requests using Libcloud http layer.

Also refactor existing drivers which use xmlrpclib directly (VCL, Gandi,
Softlayer) to use this module.

This change allows drivers to support LIBCLOUD_DEBUG and SSL certificate
validation functionality. Previously they have bypassed Libcloud http
layer so this functionality was not available.

Contributed by John Carr, part of LIBCLOUD-288.


git-svn-id: https://svn.apache.org/repos/asf/libcloud/trunk@1442533 13f79535-47bb-0310-9956-ffa450edef68
Python 2.5 compatibility fix.


git-svn-id: https://svn.apache.org/repos/asf/libcloud/trunk@1442536 13f79535-47bb-0310-9956-ffa450edef68