Replaces __builtin__ with six.moves.builtins
Replaces __builtin__ with six.moves.builtins

__builtin__ does not exist in Python 3. Replacing it with
six.moves.builtins will ensure compatibility with both Python 2.7
and Python 3.4.

Partially implements blueprint: nova-python3-mitaka

Change-Id: If99c9670644f95e2b5c37d14fad491d829850f36

Juniper/nova,NeCTAR-RC/nova,mahak/nova,openstack/nova,gooddata/openstack-nova,jianghuaw/nova,NeCTAR-RC/nova,openstack/nova,cernops/nova,rajalokan/nova,sebrandon1/nova,cyx1231st/nova,gooddata/openstack-nova,rahulunair/nova,Juniper/nova,mikalstill/nova,rahulunair/nova,klmitch/nova,BeyondTheClouds/nova,hanlind/nova,bigswitch/nova,mahak/nova,phenoxim/nova,rajalokan/nova,zhimin711/nova,vmturbo/nova,cloudbase/nova,CEG-FYP-OpenStack/scheduler,openstack/nova,vmturbo/nova,vmturbo/nova,rajalokan/nova,CEG-FYP-OpenStack/scheduler,rajalokan/nova,mahak/nova,phenoxim/nova,dims/nova,jianghuaw/nova,alaski/nova,mikalstill/nova,gooddata/openstack-nova,cloudbase/nova,Juniper/nova,klmitch/nova,rahulunair/nova,alaski/nova,sebrandon1/nova,cernops/nova,gooddata/openstack-nova,klmitch/nova,BeyondTheClouds/nova,cernops/nova,mikalstill/nova,sebrandon1/nova,zhimin711/nova,hanlind/nova,jianghuaw/nova,klmitch/nova,vmturbo/nova,BeyondTheClouds/nova,bigswitch/nova,hanlind/nova,Juniper/nova,cloudbase/nova,cyx1231st/nova,jianghuaw/nova,dims/nova