Get cmd uses print-column extn from Openapi schema

Get command now uses metadata x-kubernetes-print-columns, if present, in Openapi schema
to format output for a resource. This functionality is guarded by a boolean
flag 'use-openapi-print-columns'.

pkg/kubectl/cmd/util/openapi/openapi.go

@@ -194,7 +194,7 @@ func (o *Resources) parseDefinition(name string, s spec.Schema) Kind {
 		Fields:           map[string]Type{},
 	}
 	if err != nil {
-		glog.Warning(err)
+		glog.V(2).Info(err)
 	}
 
 	// Definition represents a primitive type - e.g.