Fix middleware logging for swift
Fix middleware logging for swift

Swift sets 'log_name' in the conf, and this can be used to set the
correct logger.  This patch moves the log configuration to
initialization so that the logger can be set appropriately and the
middleware will log to the swift proxy logs.  This also requires the
following review in swift to work:
https://review.openstack.org/#/c/17983/

Fixes bug #1089664

Change-Id: I315102ba277ac1f5ff92f4d79ae745bf53559328

klmitch/python-keystoneclient,ntt-sic/python-keystoneclient,jamielennox/python-keystoneclient,Mercador/python-keystoneclient,jamielennox/python-keystoneclient,ntt-sic/python-keystoneclient,magic0704/python-keystoneclient,citrix-openstack-build/python-keystoneclient,darren-wang/ksc,ging/python-keystoneclient,citrix-openstack-build/python-keystoneclient,klmitch/python-keystoneclient,darren-wang/ksc,alexpilotti/python-keystoneclient,ging/python-keystoneclient,sdpp/python-keystoneclient,magic0704/python-keystoneclient,citrix-openstack-build/python-keystoneclient,sdpp/python-keystoneclient,Mercador/python-keystoneclient,jamielennox/python-keystoneclient,metacloud/python-keystoneclient,ntt-sic/python-keystoneclient,metacloud/python-keystoneclient,alexpilotti/python-keystoneclient