Implement networks routed through wesher

This adds an option for specifying a routed network. Every node route
that belongs to that routed network will be announced to the cluster and
every other node will direct traffic to that node for said route.

tests/e2e.sh

@@ -127,6 +127,20 @@ test_multiple_clusters_restart() {
     stop_test_container test1-orig
 }
 
+test_routed_network() {
+    run_test_container test1-orig test1 --init --routed-net 10.15.0.0/16
+    run_test_container test2-orig test2 --join test1-orig --routed-net 10.15.0.0/16
+    docker exec test2-orig bash -c "ip l a test type bridge; ip l s up test; ip a a 10.15.0.1/24 dev test"
+
+    sleep 3
+
+    docker exec test1-orig ping -c1 -W1 test2 || (docker logs test1-orig; docker logs test2-orig; false)
+    docker exec test1-orig ping -c1 -W1 10.15.0.1 || (docker logs test1-orig; docker logs test2-orig; false)
+
+    stop_test_container test2-orig
+    stop_test_container test1-orig    
+}
+
 for test_func in $(declare -F | grep -Eo '\<test_.*$'); do
     echo "--- Running $test_func:"
     $test_func