proper names for constants; some clean up for log messages

cmd/main.go

pkg/cluster/cluster.go

pkg/cluster/filesystems.go

pkg/cluster/k8sres.go

pkg/cluster/pod.go

pkg/cluster/resources.go

pkg/cluster/sync.go

pkg/cluster/util.go

pkg/cluster/volumes.go

pkg/controller/pod.go

pkg/controller/postgresql.go

pkg/controller/util.go

pkg/spec/postgresql_test.go

pkg/spec/types_test.go

pkg/util/constants/kubernetes.go

pkg/util/constants/roles.go

pkg/util/constants/thirdpartyresource.go

pkg/util/filesystems/ext234.go

pkg/util/k8sutil/k8sutil.go

pkg/util/users/users.go