Description of hypervisor configuration options

Configuration option = Default value	Description
[DEFAULT]
default_ephemeral_format = None	(StrOpt) The default format an ephemeral_volume will be formatted with on creation.
force_raw_images = True	(BoolOpt) Force backing images to raw format
preallocate_images = none	(StrOpt) VM image preallocation mode: "none" => no storage provisioning is done up front, "space" => storage is fully allocated at instance start
timeout_nbd = 10	(IntOpt) Amount of time, in seconds, to wait for NBD device start up.
use_cow_images = True	(BoolOpt) Whether to use cow images
vcpu_pin_set = None	(StrOpt) Defines which pcpus that instance vcpus can use. For example, "4-12,^8,15"
virt_mkfs = []	(MultiStrOpt) Name of the mkfs commands for ephemeral device. The format is <os_type>=<mkfs command>