Add nova configuration reference tables

This is the first attempt at automatically generated configuration
tables being added to documentation.
blueprint autogenerate-config-tables
https://wiki.openstack.org/wiki/Blueprint-autogenerate-config-tables

Work is being conducted out-of-repo at :

https://github.com/fifieldt/autogenerate-config-docs

Nova has existing tables, which are out of date for Grizzly.

Patchset 2:

Based on positive feedback, patchset 2 links in the tables to the
Compute Administration Guide, expanding its configuration reference,
adding config option sections to areas that lacked them and
removing old tables.

Patchset 3/4 just updates the author's email address.

Cherry-picked from https://review.openstack.org/#/c/28904/

Change-Id: I2c400fa511df5c878c5b640085a6e5286b1dd318
Merge "Add nova configuration reference tables" into stable/grizzly