* add_api_cn (#437)

* add gpu benchmark page (#436)

* add gpu benchmark

* fix comments

* add chinese link in gen_doc.py (#439)

* modified gen_doc.py

* Update gen_doc.py

* update gen_doc.py

* Update mobile doc (#440)

* update_en_structure

* update_Paddle_commitid

* delete_DS

* update_mobile_doc

* Update book commit (#438)

* update_en_structure

* update_Paddle_commitid

* delete_DS

* update_book_commit_id

* update_api_rst

* Adjust structure of advanced usage (#442)

* adjust_structure_of_advanced_usage

* Update paddle_gpu_benchmark.md

* adjust_toctree_hidden

* fix_api_guide

* Update index.rst

* fix deadlinkes (#443)

* add_toctree (#445)

* adjust_beginners_structure (#446)

* adjust_beginners_structure

* Update index.rst

* update install_doc for python3 (#418)

* update install_doc for python3

* update python3.5+ info,test=develop

* fix review, test=develop

* fix_pic (#447)

* update install_doc for python3

* update python3.5+ info,test=develop

* fix review, test=develop

* Update install_Ubuntu.md

* Update install_MacOS.md

* Update install_CentOS.md

* Update install_Windows.md

* Update compile_CentOS.md

* Update compile_MacOS.md

* Update compile_Ubuntu.md

* renew the install doc for V1.0

* refine doc

* refine MAC_compile with user installed openblas

* fix python3 related issue according to https://github.com/PaddlePaddle/Paddle/issues/13724

* refine python3 LD_LIBRARY and DYLD_LIBRARY set

* fix FAQ

* refine macos compile and install on python settings

* refine mac compile command

* fix comment related format problem

* fix FAQ format problem

* add mac compile on 10.14

* remove py3 compile on mac 10.14

* refine