improve TFPark readme (#1684)

* improve readme

* fix path

* change sh to bash

python/orca/example/tfpark/README.md

@@ -25,12 +25,14 @@ export PYTHONPATH=$PWD/models/research/slim:$PYTHONPATH
 Using TFDataset as data input
 
 ```bash
-python keras_dataset.py
+export MASTER=local[4]
+python keras/keras_dataset.py
 ```
 
 Using numpy.ndarray as data input
 ```bash
-python keras_ndarray.py
+export MASTER=local[4]
+python keras/keras_ndarray.py
 ```
 
 ## Run the KerasModel example with prebuilt package
@@ -41,21 +43,22 @@ Using TFDataset as data input
 export ANALYTICS_ZOO_HOME=... # the directory where you extract the downloaded Analytics Zoo zip package
 export SPARK_HOME=... # the root directory of Spark
 
-sh $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] keras/keras_dataset.py
+bash $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] keras/keras_dataset.py
 ```
 
 Using numpy.ndarray as data input
 ```bash
 export ANALYTICS_ZOO_HOME=... # the directory where you extract the downloaded Analytics Zoo zip package
 export SPARK_HOME=... # the root directory of Spark
 
-sh $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] keras/keras_ndarray.py
+bash $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] keras/keras_ndarray.py
 ```
 
 ## Run the TFEstimator example after pip install
 
 Using TFDataset as data input
 ```bash
+export MASTER=local[4]
 python estimator/estimator_dataset.py
 ```
 
@@ -65,17 +68,17 @@ Using FeatureSet as data input
 # the directory to the training data, the sub-directory of IMAGE_PATH should be
 # different classes each containing the images of that class.
 # e.g.
-# IMAGE_PATH=/cat_dog
+# IMAGE_PATH=file:///cat_dog
 # NUM_CLASSES=2
 # /cat_dog
 #    /cats
 #       cat.001.jpg
 #    /dogs
 #       dog.001.jpg
-IMAGE_PATH=...
+IMAGE_PATH=... # file://... for local files and hdfs:// for hdfs files
 NUM_CLASSES=..
 
-
+export MASTER=local[4]
 python estimator/estimator_inception.py --image-path $IMAGE_PATH --num-classes $NUM_CLASSES
 ```
 
@@ -86,7 +89,7 @@ Using TFDataset as data input
 export ANALYTICS_ZOO_HOME=... # the directory where you extract the downloaded Analytics Zoo zip package
 export SPARK_HOME=... # the root directory of Spark
 
-sh $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] estimator/estimator_dataset.py
+bash $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] estimator/estimator_dataset.py
 ```
 
 Using FeatureSet as data input
@@ -99,18 +102,18 @@ export SPARK_HOME=... # the root directory of Spark
 # the directory to the training data, the sub-directory of IMAGE_PATH should be
 # different classes each containing the images of that class.
 # e.g.
-# IMAGE_PATH=/cat_dog
+# IMAGE_PATH=file:///cat_dog
 # NUM_CLASSES=2
 # /cat_dog
 #    /cats
 #       cat.001.jpg
 #    /dogs
 #       dog.001.jpg
-IMAGE_PATH=...
+IMAGE_PATH=... # file://... for local files and hdfs:// for hdfs files
 NUM_CLASSES=..
 
 
-sh $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] estimator/estimator_inception.py --image-path $IMAGE_PATH --num-classes $NUM_CLASSES
+bash $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] estimator/estimator_inception.py --image-path $IMAGE_PATH --num-classes $NUM_CLASSES
 ```
 
 ## Run the Training Example using TFOptimizer after pip install
@@ -131,7 +134,7 @@ python tf_optimizer/train_mnist_keras.py
 export ANALYTICS_ZOO_HOME=... # the directory where you extract the downloaded Analytics Zoo zip package
 export SPARK_HOME=... # the root directory of Spark
 
-sh $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] tf_optimizer/train_lenet.py
+bash $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] tf_optimizer/train_lenet.py
 ```
 
 For Keras users:
@@ -140,7 +143,7 @@ For Keras users:
 export ANALYTICS_ZOO_HOME=... # the directory where you extract the downloaded Analytics Zoo zip package
 export SPARK_HOME=... # the root directory of Spark
 
-sh $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] tf_optimizer/train_mnist_keras.py
+bash $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] tf_optimizer/train_mnist_keras.py
 ```
 
 ## Run the Evaluation Example using TFPredictor after pip install
@@ -161,7 +164,7 @@ python tf_optimizer/evaluate_mnist_keras.py
 export ANALYTICS_ZOO_HOME=... # the directory where you extract the downloaded Analytics Zoo zip package
 export SPARK_HOME=... # the root directory of Spark
 
-sh $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] tf_optimizer/evaluate_lenet.py
+bash $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] tf_optimizer/evaluate_lenet.py
 ```
 
 For Keras users:
@@ -170,5 +173,5 @@ For Keras users:
 export ANALYTICS_ZOO_HOME=... # the directory where you extract the downloaded Analytics Zoo zip package
 export SPARK_HOME=... # the root directory of Spark
 
-sh $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] tf_optimizer/evaluate_mnist_keras.py
-```
+bash $ANALYTICS_ZOO_HOME/bin/spark-submit-python-with-zoo.sh --master local[4] tf_optimizer/evaluate_mnist_keras.py
+```