This removes the majority of the nova-volume code from the codebase.
It updates relevent config options to default to cinder. It updates a
number of existing tests that were depending on code that was removed.

A few things still need to be removed:

 * volume/driver.py & volume/iscsi.py
   These files are used by the libvirt volume driver tests. These
   tests should be updated to mock the relevant calls.

 * scheduler/simple.py & scheduler/multi.py
   These files should no longer be necessary so they can be removed
   in a subsequent patch

 * exception.py cleanup
   Once the above files are removed there are a number of unused
   exceptions which can be removed

 * database calls and database tables
   The database calls have not been removed and the tables have not
   been dropped. This can be done in a separate migration

 * additional config options and nova.conf.sample
   There may be a few extra config options that can be removed and the
   conf sample can be regenerated

Implements bp delete-nova-volume

Change-Id: I0b540e54dbabd26901a7530035a38583bb521fda

Replace hardcoded topic strings like 'volume' or 'compute'
with config constants like FLAGS.volume_topic, etc. See
bug #1057831 and bug #1061628.

Change-Id: I817ecc3cbe3245b51a0c047be58d17edfec8a838

I only just moved logging from nova to common, so behavior should remain the same.

Change-Id: I1d7304ca200f9d024bb7244d25be2f9a670318fb

Implements blueprint cfg-global-object

Replace nova.flags.FLAGS with openstack.common.cfg.CONF.

In future, we can do a s/FLAGS/CONF/ across the codebase.

Change-Id: Ib293873089a5399febd7a3b0410f66e9bef115f1

Implements blueprint remove-old-flagfile

nova-manage can still be used to convert old flagfiles style files
to new .ini files:

$ ./bin/nova-manage  config  convert --help
Usage: nova-manage config convert <args> [options]

Options:
  -h, --help        show this help message and exit
  --infile=<path>   old-style flagfile to convert to config
  --outfile=<path>  path for output file. Writes configto stdout if not
                    specified.

Change-Id: Ib8fbbd858b1db7faef70d7d97955e5042bf378f2
Signed-off-by: Ghe Rivero <ghe@debian.org>