Update Makefile

add back py-example-adder

Author: longhathuc

Makefile

@@ -64,7 +64,7 @@ SUBDIR+=	py-dynamic-graph-bridge-v3
 SUBDIR+=	py-dynamic-graph-tutorial
 SUBDIR+=	py-dynamic-graph-v3
 SUBDIR+=	py-ecos
-#SUBDIR+=	py-example-adder
+SUBDIR+=	py-example-adder
 SUBDIR+=	py-gurobi
 SUBDIR+=	py-hqp
 SUBDIR+=	py-hpp-affordance-corba