Use UUID version 1 for new instances

This blueprint has the target to propose the possibility to generate an UUID for new instances using version 1 algorithm as described in RFC 4122 (http://www.ietf.org/rfc/rfc4122.txt) and giving to the user the chance to set the "node" field of the UUID.

Currently the UUID for a newly created instance is generated with a (pseudo)random algorithm, according to version 4 described in RFC 4122, anyway this is not the only algorithm supported in the standard.

In the RFC4122 an UUID is described with this this form:

UUID = time-low "-" time-mid "-"
                                         time-high-and-version "-"
                                         clock-seq-and-reserved
                                         clock-seq-low "-" node
time-low = 4hexOctet
time-mid = 2hexOctet
time-high-and-version = 2hexOctet
clock-seq-and-reserved = hexOctet
clock-seq-low = hexOctet
node = 6hexOctet
hexOctet = hexDigit hexDigit
hexDigit =
            "0" / "1" / "2" / "3" / "4" / "5" / "6" / "7" / "8" / "9" /
            "a" / "b" / "c" / "d" / "e" / "f" /
            "A" / "B" / "C" / "D" / "E" / "F"

In version 1 UUID the "time" part rappresent a time stamp, the clock sequence is to help to avoid duplicate (can be randomly generated) and the node is a sequence in the form of an IEEE 802 MAC address.

This blueprint proposal is to add an optional "node_uuid" parameter to the "Create server" request and use the value of this parameter as the node field of the UUID assigned to the server; if the parameter "node_uuid" is not present, the UUID will be generated normally with the version 4 algorithm.

This blueprint follows the discussion started via the developer mailing list http://lists.openstack.org/pipermail/openstack-dev/2014-September/046979.html