This pull request adds "Build using Docker" documentation to the "Getting Started > Install and Build" menu on PaddlePaddle.org

Change the instructions to use https instead of SSH

* 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

Update the write_docs_en.rst and write_docs_cn.rst to include how to run the documentation viewer tool without Docker
Add dev/contribute_to_paddle_cn.md onto navigation link

* 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.