Avalanche tree added to distributed data

doc/avalanche.fig

-#FIG 3.2  Produced by xfig version 3.2.5b
+#FIG 3.2  Produced by xfig version 3.2.7b
 Landscape
 Center
 Metric
-A4      
+A4
 100.00
 Single
 -2
@@ -145,6 +145,8 @@ Single
 	 5175 2700 5625 2700 5625 3150 5175 3150 5175 2700
 2 2 0 1 0 2 50 -1 20 0.000 0 0 -1 0 0 5
 	 1575 2700 2025 2700 2025 3150 1575 3150 1575 2700
+2 2 0 1 0 0 60 -1 20 0.000 0 0 7 0 0 5
+	 450 450 12600 450 12600 6750 450 6750 450 450
 3 2 0 1 4 4 50 -1 -1 0.000 0 1 0 3
 	1 1 1.00 60.00 120.00
 	 6975 2700 5625 2250 4725 2700