ciao-controller: Check names are unique when creating instance
ciao-controller: Check names are unique when creating instance

Check that the name is unique when instances are being created. This is
required as we start to allow instance names to be used in place of
UUIDs and for the the DNS.

Fixes: #1263

Signed-off-by: Rob Bradford <c49e1dc14cd52e2644816db47123896e0ac79025@intel.com>

01org/ciao,01org/ciao,tpepper/ciao,ciao-project/ciao,rbradford/ciao,rbradford/ciao,kaccardi/ciao,tpepper/ciao,mcastelino/ciao,kaccardi/ciao,mcastelino/ciao,mcastelino/ciao,markdryan/ciao,markdryan/ciao,tpepper/ciao,ciao-project/ciao