Update DS2 README.md

Author: xinghai-sun

deep_speech_2/README.md

@@ -1,8 +1,6 @@
 # Deep Speech 2 on PaddlePaddle
 
-## Quick Start
-
-### Installation
+## Installation
 
 Please replace `$PADDLE_INSTALL_DIR` with your paddle installation directory.
 
@@ -13,7 +11,9 @@ export LD_LIBRARY_PATH=$PADDLE_INSTALL_DIR/Paddle/third_party/install/warpctc/li
 
 For some machines, we also need to install libsndfile1. Details to be added.
 
-### Preparing Dataset(s)
+## Usage
+
+### Preparing Data
 
 ```
 cd data