* fixed one error

* fixed op error

* fixed five errors of api_cn.

* fixed one error of api_cn

* fixed some errors of api_cn

* fixed two links.

* fixed one link.

* fixed one error.

* fixed some links.

* fixed some links of http://newicafe.baidu.com/issue/DLTP-1529/show?from=page.

* fixed the return of yolo_box,http://newicafe.baidu.com/issue/DLTP-1647/show?from=page

* fixed the return of yolo_box,http://newicafe.baidu.com/issue/DLTP-1647/show?from=page

* fixed one error,http://newicafe.baidu.com/issue/DLTP-1771/show?from=page

* fixed one error,http://newicafe.baidu.com/issue/DLTP-1907/show?from=page

* http://newicafe.baidu.com/issue/DLTP-1026/show?from=page

* fixed the link of lstmp

* modify write_docs_cn, write_docs_en, include specifications about python 2.7.15 and creating  virtual env with conda

* gitignore update

* revert .gitignore;  update write_docs

* icafe DLTP-1328, stress  exe.close()

* DLTP-1383 不可迭代更正

* DLTP-1404 修复动态图文档中每段代码的格式和大小都不一样

* DLTP-1390 Pyreader中文显示格式问题

* DLTP-1393 无效链接

* DLTP-1421 paddle.fluid.layers.reduce_max中文翻译有问题

* DyGraph 调整标签结构

* add gpu dist train best practice

* fix styles

* update

* update