CORD-160 Add connect and disconnect methods to ovsdb

Change-Id: I66e777f8ec9c5834e27b1dc685fdeb197e30ce0d
diff --git a/ovsdb/api/src/main/java/org/onosproject/ovsdb/controller/driver/DefaultOvsdbClient.java b/ovsdb/api/src/main/java/org/onosproject/ovsdb/controller/driver/DefaultOvsdbClient.java
index 0c64cc0..1b41be9 100644
--- a/ovsdb/api/src/main/java/org/onosproject/ovsdb/controller/driver/DefaultOvsdbClient.java
+++ b/ovsdb/api/src/main/java/org/onosproject/ovsdb/controller/driver/DefaultOvsdbClient.java
@@ -821,7 +821,7 @@
             Function<JsonNode, DatabaseSchema> rowFunction = new Function<JsonNode, DatabaseSchema>() {
                 @Override
                 public DatabaseSchema apply(JsonNode input) {
-                    log.info("Get ovsdb database schema", dbName);
+                    log.info("Get ovsdb database schema {}", dbName);
                     DatabaseSchema dbSchema = FromJsonUtil
                             .jsonNodeToDbSchema(dbName, input);
                     if (dbSchema == null) {
@@ -1185,4 +1185,10 @@
         }
         return ifaceid;
     }
+
+    @Override
+    public void disconnect() {
+        channel.disconnect();
+        this.agent.removeConnectedNode(nodeId);
+    }
 }