Merge pull request #25 from stackhpc/fix/pip

rebuild: upgrade pip during install

Author: sjpb

roles/rebuild/tasks/main.yml

@@ -29,7 +29,7 @@
     - name: install slurm-openstack-tools
       shell: |
         source /opt/slurm-tools/bin/activate
-        pip install pip
+        pip install -U pip
         pip install git+https://github.com/stackhpc/slurm-openstack-tools.git
       args:
         creates: /opt/slurm-tools/bin/slurm-openstack-rebuild