* update mobile doc

* Update mobile_readme.md

* Update mobile_dev.md

* Rename mobile_dev.md to development_ios.md

* Update index_mobile.rst

* Delete development_ios.md

* Update index_mobile.rst

* Update mobile_readme.md

* windows doc

* fix comment. test=develop

* create how to write docs

* Update write_docs_cn.md

* Update write_docs_cn.md

* Update write_docs_cn.md

* Update fluid_design_idea.md

* 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

* add metrics api guide

* update metrics.rst

* update metrics.rst

* update metrics.rst

* update metrics.rst

* update metrics.rst

* update metrics.rst