initial pass at template mirroring script

To use this mirror script

1. Start the control center master (eg serviced.example.com)
2. Download the mirror script: curl -k https://serviced.example.com/static/scripts/template-mirror.py -O
3. chmod +x template-mirror.py
4. template-mirror.py /opt/serviced/templates/zenoss-resmgr-5.0.0_652.json serviced.example.com:5000 /opt/serviced/templates/zenoss-resmgr-5.0.0_652_serviced.example.com.json
5. serviced template add /opt/serviced/templates/zenoss-resmgr-5.0.0_652_serviced.example.com.json

Then, the template will be loaded and will reference Images hosted on the serviced hosted docker registry only.