Implement Merge on Read Storage (#76)

1. Create HoodieTable abstraction for commits and fileSystemView
2. HoodieMergeOnReadTable created
3. View is now always obtained from the table and the correct view based on the table type is returned

hoodie-client/src/main/java/com/uber/hoodie/exception/HoodieAppendException.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2016 Uber Technologies, Inc. (hoodie-dev-group@uber.com)
+ *
+ * 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 com.uber.hoodie.exception;
+
+/**
+ * <p>
+ * Exception thrown for any higher level errors when <code>HoodieClient</code> is doing a delta commit
+ * </p>
+ */
+public class HoodieAppendException extends HoodieException {
+    public HoodieAppendException(String msg, Throwable e) {
+        super(msg, e);
+    }
+
+    public HoodieAppendException(String msg) {
+        super(msg);
+    }
+}