tsrelay/handler: change nodes to machines (#188)

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Fixes #187

---------

Co-authored-by: Marwan Sulaiman <marwan.sameer@gmail.com>

tsrelay/handler/get_peers.go

@@ -71,9 +71,9 @@ func (h *handler) getPeers(ctx context.Context, body io.Reader) (*getPeersRespon
 
 	s := getPeersResponse{PeerGroups: []*peerGroup{}}
 	peerGroups := [...]*peerGroup{
-		{Name: "My nodes"},
-		{Name: "All nodes"},
-		{Name: "Offline nodes"},
+		{Name: "Managed by you"},
+		{Name: "All machines"},
+		{Name: "Offline machines"},
 	}
 
 	if st.BackendState == "NeedsLogin" || (st.Self != nil && !st.Self.Online) {