This adds a parameter '--lvm_thin' to xen-create-image that allows you to specify the thin pool where the thin logical volumes will be created. If '--lvm_thin' is not specified, nothing will change and thick provisioned volumes will be created. [Committer's note: Code logic taken from https://github.com/youknow0/xen-tools-thin-provisioning/commit/a6f267ef and adapted to current code. Needed more than just a rebase. All trailing whitespace has been removed, too.] Fixes xen-tools/xen-tools#47.