Fix swift3 middleware entry point.

- Fixes bug 1015071.

Change-Id: I969d8826b2a2633488d6eac321e1f52bd47bf7f8
diff --git a/stack.sh b/stack.sh
index 71c2f9e..4d922a5 100755
--- a/stack.sh
+++ b/stack.sh
@@ -1497,7 +1497,7 @@
 admin_password = ${SERVICE_PASSWORD}
 
 [filter:swift3]
-use = egg:swift3#middleware
+use = egg:swift3#swift3
 EOF
 
     cp ${SWIFT_DIR}/etc/swift.conf-sample ${SWIFT_CONFIG_DIR}/swift.conf