Prevent updating UUID of Node, Port and Chassis on DB API level

UUID is seen as something similar to pkey and is not expected
to be updated after creation.
This patch makes update_{node,chassis,port} raise InvalidParameterValue,
if 'uuid' field is passed in.

Closes-Bug: #1333683
Change-Id: I7312036a5144cebe3da7f033f73e881e79e8a2ca
Merge "Prevent updating UUID of Node, Port and Chassis on DB API level"