Updated openstack/openstack
Project: openstack/heat  9a8ffd1ef8d9ca362828c3bde9696d1279b8fff6
null
Replace '+' with string interpolation operation

Replace string concatenation of translated messages with string
interpolation operation, since the gettextutils.Message object
doesn't support the '+' operation, which will cause problem when
lazy translation is enalbed.

Change-Id: I2c8a271ef766ab0da81b1c320870bbc429f6207e