* When execute `nvme connect`, "host-nqn" is needed in RSD environment.
So add it as an optional parameter.
* It is observed that the first `nvme list` can miss the newly connected
nvme device, right after a success call of `nvme connect`. The
solution is to add the retry&sleep logic back.
* Sometimes there can be more than 10 nvme devices, e.g.
"/dev/nvme10n10". Need to update the device re pattern.
* In RSD environment, the connector needs additional information like
"system uuid", to let cinder-volume know the nova-cpu service is
running on which RSD node.
* Add a new protocol "NVMEOF" mapping to allow both Cinder and Nova to
identify and use the nvme connector.
Implements: blueprint nvme-volume-driver
Change-Id: I26e3dc140b2cf30a97665679fdc4d2f897cd4872