* Make ocr and icnet support for python3

* Restore default arguments.

* Add icnet.

* Fix code.

* Fix utils.py.

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

1. Move all network defining to 'crnn_ctc_model.py'
2. Add initilizer for some layers
3. Rename 'fluid/ocr' to 'fluid/ocr_recognition'
4. Remove copyright
5. Rename some functions

1. Remove 'ocr_ctc' directory to 'ocr'.
2. Init README.md
3. Fix learning rate and l2
4. Refine training log format
5. Reduce arguments of train function
6. Set filter_size of im2sequence dynamicly
7. Add fc op before GRU op