HUDI-123 Rename code packages/constants to org.apache.hudi (#830)

- Rename com.uber.hoodie to org.apache.hudi
- Flag to pass com.uber.hoodie Input formats for hoodie-sync
- Works with HUDI demo. 
- Also tested for backwards compatibility with datasets built by com.uber.hoodie packages
- Migration guide : https://cwiki.apache.org/confluence/display/HUDI/Migration+Guide+From+com.uber.hoodie+to+org.apache.hudi

hudi-spark/src/test/java/DataSourceTestUtils.java

@@ -0,0 +1,46 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+import java.io.IOException;
+import java.util.List;
+import java.util.stream.Collectors;
+import org.apache.hudi.common.TestRawTripPayload;
+import org.apache.hudi.common.model.HoodieRecord;
+import org.apache.hudi.common.util.Option;
+
+/**
+ * Test utils for data source tests.
+ */
+public class DataSourceTestUtils {
+
+  public static Option<String> convertToString(HoodieRecord record) {
+    try {
+      String str = ((TestRawTripPayload) record.getData()).getJsonData();
+      str = "{" + str.substring(str.indexOf("\"timestamp\":"));
+      return Option.of(str.replaceAll("}",
+          ", \"partition\": \"" + record.getPartitionPath() + "\"}"));
+    } catch (IOException e) {
+      return Option.empty();
+    }
+  }
+
+  public static List<String> convertToStringList(List<HoodieRecord> records) {
+    return records.stream().map(hr -> convertToString(hr)).filter(os -> os.isPresent())
+        .map(os -> os.get()).collect(Collectors.toList());
+  }
+}