VendorPassthru commands to support different HTTP methods

Extend the vendor_passthru() library methods and clients to support
issuing different HTTP methods on the vendor endpoints.

Implements: blueprint extended-vendor-passthru
Change-Id: I32a4990ed3db0bc73ce845b9b4119d87ab2e1503
Add option to specify node uuid in node-create subcommand

- node-create subcommand now includes -u or --uuid
option that allows the user to specify the uuid if
needed.

- The uuid parameter is optional

Change-Id: I1a8332689d6d5f85350877bd4ab64aa173e5d916
Closes-Bug: 1381214
Merge "VendorPassthru commands to support different HTTP methods"