LUCreateInstance: only set running flag at the end
LUCreateInstance: only set running flag at the end

In lockless queries, it's better if we see the instance in ADMIN_down
rather than ERROR_down during the time it's installed. As such, we
change the LU to only mark the instance 'up' at the time we are ready to
start it.

Reviewed-by: ultrotter

mbakke/ganeti,grnet/snf-ganeti,bitemyapp/ganeti,ganeti-github-testing/ganeti-test-1,ganeti-github-testing/ganeti-test-1,ganeti/ganeti,apyrgio/snf-ganeti,leshchevds/ganeti,onponomarev/ganeti,mbakke/ganeti,ganeti/ganeti,apyrgio/ganeti,grnet/snf-ganeti,leshchevds/ganeti,dimara/ganeti,yiannist/ganeti,yiannist/ganeti,andir/ganeti,ganeti/ganeti,andir/ganeti,andir/ganeti,bitemyapp/ganeti,apyrgio/snf-ganeti,mbakke/ganeti,apyrgio/ganeti,yiannist/ganeti,dimara/ganeti,onponomarev/ganeti,leshchevds/ganeti