* Add optional Glance and Neutron integration.
* Migrate and expand the configdrive section from the install guide.
* Explain how to use cloud-init boot scripts.
* Explain allocations and mention metalsmith as an easy CLI.
* Use more realistic URLs and checksums in the examples.
* Remove a reference to local boot, it's the default nowadays.
* Replace the iLO note with a more generic one.
* Small fixes and clean ups.
Change-Id: I28ac60da6722b9ca2c2b571511070010145958f6