add CTC module

[anxingle]

It is very helpful to see your tutorial code . Thanks very much. But I want to add CTC module,so it will more powerful. I write as the Blog write.
My code is using LSTM to classify Mnist data . But CTC_LOSS don't work at all. Can you help me define the right call style? The code is based on your Tensorflow-101 and I promise U can get it when you see the code .