* Refine code for English dataset.
1. Remove a pooling layer.
2. Change classes_num to 94.
3. Modify some arguments in ctc_train.py
4. Add learning rate decay policy.

* Fix readme.

* Fix README.

* Remove consine decay.

* Remove eval.sh

1. Remove unused  arguments.
2. Refine doc.
3. Change 'device' to 'use_gpu'.

1. Add document.
2. Add arguments for saving model and init model.
3. Refine inference.py and eval.py.
4. Make ctc_reader.py support for custom data.

2. Add inference script
3. Add load model script
4. Add some functions into ctc_reader