With the release of 1.5.2, CUDA and CUDnn support will also need to be updated for Windows installation.
There are following changes:

    Release of 1.5.2 support CUDA10,
    CUDA8 should match up cuDNN v7.1+,
    The path Settings on CMAKE command line have been explained in detail.

Note: this PR is the sum of PR#1142 and PR#1051 on develop branch.

* fix error for install doc in release/1.5, test=release/1.5

* fix for install doc in release/1.5, test=release/1.5

* fix for install doc in release/1.5, test=release/1.5

* fix for install doc in release/1.5, test=release/1.5

* fixed one error

* faq

* flags classify and delete releasenotes

* 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

* fixed link error for compile_Ubuntu.md in release/1.5

* fixed link error for install doc in release/1.5

* 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.

* cherry-pick fix from dev

* refine isntall doc with version explaination on CUDA

* refine isntall doc with version explaination on CUDA

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* synchronize api_en and api_cn

* fix bug

* Update nn_cn.rst

*  fix for install doc in release/1.5

* fix for install doc in release/1.5

* fix for install doc into release/1.5

* fix for install doc into release/1.5

* fix for install doc into release/1.5

* fix some error

* add releasenotes and models

* add releasenotes en version

* dygraph translation

* cn doc bug fix

* translate dygraph according to 1.5.1 website + bug fix

* update 1.5.1 cn API

* add url

* test=develop, add fix_install_doc_with_gpu_docker_usage (#1007)

* test=develop, add fix_install_doc_with_gpu_docker_usage

* refine format

* fix install command wrong

* fix some problem in install doc (#1008)

* add windows install whl

* whl and bug

* fix some bugs

compile_CentOS.md
compile_Ubuntu.md
install_CentOS.md
install_Ubuntu.md

* add best practice

* polish doc