Fixed dao could not find class exception during tests and added license header

+/**
+ * Copyright © 2016-2017 The Thingsboard Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 package org.thingsboard.server.dao.sql.relation;
 
 import com.google.common.util.concurrent.ListenableFuture;

@@ -20,6 +20,7 @@ import com.github.springtestdbunit.bean.DatabaseDataSourceConnectionFactoryBean;
 import org.dbunit.DatabaseUnitException;
 import org.dbunit.ext.postgresql.PostgresqlDataTypeFactory;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 
@@ -31,6 +32,7 @@ import java.sql.SQLException;
  * Created by Valerii Sosliuk on 5/6/2017.
  */
 @Configuration
+@ConditionalOnProperty(prefix = "sql", value = "enabled", havingValue = "true")
 public class JpaDbunitTestConfig {
 
     @Autowired