Allows libvirt to set a serial number for a volume

The serial number defaults to the volume_id of the volume being
attached. We may expose a method in the future to set a different
serial number when creating or attaching a volume.

The purpose of this change is to give users a consistent place
they can find their volume. It should show up now in most flavors
of linux under /disk/by-id/virtio-<volume_uuid>

Fixes bug 1004328

Change-Id: Id1c56b5b23d799deb7da2d39ae57ecb48965c55f
Provide a hint for missing EC2 image ids

EC2 image ids are allocated when the images are listed for the first
time. Remind users of this if they specify an image id which does
not exist. Resolves bug 961451.

Change-Id: Id7326ba32e58051dbbf25c3c940fd0c9cc611ff3
Let admin list instances in vm_states.DELETED

Command 'nova list --status DELETED' returns nothing at the moment.
Make 'nova list --status DELETED' work and work for admin only.

Fixes LP Bug #1037885

Change-Id: I0bace95df713a767bb17e470e66361e1891e628c
Allow generate_sample.sh to be run from toplevel dir

I hit an issue where extract_opts.py couldn't import importutils
since it's not in my sys.path, so it's clear we need to set
PYTHONPATH before running.

The whole business of running the tool from the tools/conf dir
is fairly awkward, so change it to run from the top-level dir
instead.

Change-Id: I89b4d874a6ee3732234a9704a8ee6001a293ed71
Re-generate nova.conf.sample

It looks like this hasn't been regenerated in a looong time.

DocImpact: update nova.conf docs
Change-Id: I64832ca79b3456e64237bfa0b1b130201a3f678b
Include CommonConfigOpts options in sample config

Options defined by CommonConfigOpts are declared within the class rather
than at module level, so they weren't being included in the sample conf.

Also, in essex (and up until commit 991614add8), the sample conf file
didn't contain these options but they included the hyphen in the name.
The hyphen is only used on the command line, it is converted to an
underscore automatically in the config file. Use opt.dest rather than
opt.name as the config file key. Fixes bug #1034970.

DocImpact: update nova.conf docs
Change-Id: Ia7f3dded9148deedeb198c19a8d343db6dd93f99
Re-work the handling of firewall_driver default

Fixes bug #1040430

We have a different default firewall driver for libvirt and
xenapi, yet the sample config file currently contains:

  firewall_driver=nova.virt.firewall.IptablesFirewallDriver

In the case of libvirt, it should actually be:

  firewall_driver=nova.virt.firewall.libvirt.IptablesFirewallDriver

This is really easy for users to get confused about.

Since we don't have a different sample config file for each hypervisor,
the best we can do is to just not include the default in the sample
config and have each hypervisor supply its default at runtime.

DocImpact: update nova.conf docs
Change-Id: Ie78371bcceac5a65978d695934e0246022f748a3
Remove unused instance id-to-uuid function

This has been unused since commit 0d9d2487e2.

Change-Id: I5a3171d566da60e1d4aaadc8a442e88103501ad6
Merge "Re-generate nova.conf.sample"
Merge "Include CommonConfigOpts options in sample config"
Merge "Allows libvirt to set a serial number for a volume"
Merge "Provide a hint for missing EC2 image ids"
Merge "Re-work the handling of firewall_driver default"
Merge "Let admin list instances in vm_states.DELETED"
Merge "Allow generate_sample.sh to be run from toplevel dir"
Merge "Remove unused instance id-to-uuid function"