Delete *openstack/common* in exclude
Delete *openstack/common* in exclude

The directory openstack/common was used to keep codes from
oslo-incubator, we have retired oslo-incubator, so we needn't use
this directory any more.

Change-Id: If23d29e41fdea0c9e83331011c81a0d5b8283a27

openstack/stackviz,openstack/stackviz,openstack/stackviz