Don't allow update of ipv6-ra-mode and ipv6-address-mode

These two parameters are not updatable from the nuetron server.
And therefore for subnet-update command, they should not be displayed
in the help message.

Change-Id: I3a6abc3a4e3030d73715d55c340a77b44d41f140
Closes-Bug: #1373417
Fixes neutronclient lb-member-show command

The current lb-member-show command uses the id or name for querying.
Since the lb members do not have names, the query returns false
positives.
The unit test for id or name was removed.
Closes-Bug: #1380937
Change-Id: I804cb9d11f5208ea2d7baa58c9d878db93851517
Merge "Fixes neutronclient lb-member-show command"
Merge "Don't allow update of ipv6-ra-mode and ipv6-address-mode"