* Chage `IndicateDataType` to `GetKernelType`. Make it easier to
  understand.
* Change `OpKernelKey` to `OpKernelType`
* Make operator developers can customize which kernel the operator will
  use in runtime.

* Doc fix for smooth L1 loss

* Adding doc for softmax_op

* Added doc for softmax_with_cross_entropy

* Adding documentation for transpose_op

* small change to restart TeamCity CI

They are public now

* Change dataType to data_type

Follow PEP8

* Change name_convention to fit PEP8