Adding a config to control whether date partitioning can be assumed

- false by default
 - CAUTION: If you have an existing tables without partition metadata, you need to set this to "true"

hoodie-common/src/main/java/com/uber/hoodie/common/util/FSUtils.java

@@ -139,7 +139,7 @@ public class FSUtils {
      * Obtain all the partition paths, that are present in this table, denoted by presence of {@link
      * com.uber.hoodie.common.model.HoodiePartitionMetadata#HOODIE_PARTITION_METAFILE}
      */
-    public static List<String> getAllPartitionPaths(FileSystem fs, String basePathStr)
+    public static List<String> getAllFoldersWithPartitionMetaFile(FileSystem fs, String basePathStr)
             throws IOException {
         List<String> partitions = new ArrayList<>();
         Path basePath = new Path(basePathStr);
@@ -155,6 +155,15 @@ public class FSUtils {
         return partitions;
     }
 
+    public static List<String> getAllPartitionPaths(FileSystem fs, String basePathStr, boolean assumeDatePartitioning)
+            throws IOException {
+       if (assumeDatePartitioning) {
+           return getAllFoldersThreeLevelsDown(fs, basePathStr);
+       } else {
+           return getAllFoldersWithPartitionMetaFile(fs, basePathStr);
+       }
+    }
+
     public static String getFileExtension(String fullName) {
         Preconditions.checkNotNull(fullName);
         String fileName = (new File(fullName)).getName();