Add centos7 image for rax

Rackspace provides a centos7 image, so add it to nodepool so we can
start testing with it.  I've tested the changes from
I80024d1afdb4e40d5fe9793ab2ec443b887c5fa8 manually in this image and
it is OK.

Change-Id: I2c040cc18d61b69a6f13cf0d8d102a5994c130e4

modules/openstack_project/templates/nodepool/nodepool.yaml.erb

@@ -141,6 +141,13 @@ labels:
       - name: hpcloud-b3
       - name: hpcloud-b4
       - name: hpcloud-b5
+  - name: devstack-centos7
+    image: devstack-centos7
+    min-ready: 2
+    providers:
+      - name: rax-dfw
+      - name: rax-ord
+      - name: rax-iad
   - name: tripleo-precise
     image: tripleo-precise
     min-ready: 8
@@ -221,6 +228,13 @@ providers:
         setup: prepare_node_devstack.sh
         username: jenkins
         private-key: /home/nodepool/.ssh/id_rsa
+      - name: devstack-centos7
+        base-image: 'CentOS 7 (PVHVM)'
+        min-ram: 8192
+        name-filter: 'Performance'
+        setup: prepare_node_devstack.sh
+        username: jenkins
+        private-key: /home/nodepool/.ssh/id_rsa
   - name: rax-ord
     region-name: 'ORD'
     service-type: 'compute'
@@ -282,6 +296,13 @@ providers:
         setup: prepare_node_devstack.sh
         username: jenkins
         private-key: /home/nodepool/.ssh/id_rsa
+      - name: devstack-centos7
+        base-image: 'CentOS 7 (PVHVM)'
+        min-ram: 8192
+        name-filter: 'Performance'
+        setup: prepare_node_devstack.sh
+        username: jenkins
+        private-key: /home/nodepool/.ssh/id_rsa
   - name: rax-iad
     region-name: 'IAD'
     service-type: 'compute'
@@ -350,6 +371,13 @@ providers:
         setup: prepare_node_devstack.sh
         username: jenkins
         private-key: /home/nodepool/.ssh/id_rsa
+      - name: devstack-centos7
+        base-image: 'CentOS 7 (PVHVM)'
+        min-ram: 8192
+        name-filter: 'Performance'
+        setup: prepare_node_devstack.sh
+        username: jenkins
+        private-key: /home/nodepool/.ssh/id_rsa
   - name: hpcloud-region-a
     region-name: 'region-a.geo-1'
     service-type: 'compute'