* add doc config for fluid

* fix typo

* follow comments

* Translate the CPU profiling document

* Paragraphing

* Add survey of support of half in different CUDA versions

* small fix

* refine install docs

* do not remove files

* follow comments

* update

* Add documentation of cProfile tools

* Complete doc

* Refine code

* Updating the writeup of RNN doc

* Editing the documentation for seq_decoder, and fixing typos

* Fixing the captioning on 2 level RNN

* pushing after a pull

* Editing and re-writing parts of Data Reader design doc

* Support the build for multiple architectures at one cmake command (iOS).

* Update the documentations.

* 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.

* small fix

* fix comment

* address comment

* small fix