Tweaks to Working with Roadmaps Appendix

* Update nova-network section based on latest information
* Add a section on Nova V3 API
* tweak ironic section
* add a section on Python SDK projec

Change-Id: Iad3a86db616d0c879c1e34c8960fc997e3632843
Merge "Tweaks to Working with Roadmaps Appendix"