Document the newly added env variable (#13049)
Document the newly added env variable (#13049)

* add env variable to choose deterministic cudnn alg

* set default value to false

* fix build failure in Windows GPU

* revert the previous change

* only check determinism in CUDNN 7.x release

* Add cudnn version check

* fix lint error

* document env variable MXNET_ENFORCE_DETERMINISM

* use cudnnGet instead of cudnnFind when determinism required

* Revert "use cudnnGet instead of cudnnFind when determinism required"

This reverts commit d1bdf0f38f50b8c499f22ae1d50770b819f27678.

larroy/mxnet,zhreshold/mxnet,ForkedReposBak/mxnet,larroy/mxnet,dmlc/mxnet,ForkedReposBak/mxnet,tlby/mxnet,DickJC123/mxnet,larroy/mxnet,apache/incubator-mxnet,leezu/mxnet,eric-haibin-lin/mxnet,zhreshold/mxnet,larroy/mxnet,zhreshold/mxnet,ForkedReposBak/mxnet,ptrendx/mxnet,ForkedReposBak/mxnet,ptrendx/mxnet,tlby/mxnet,eric-haibin-lin/mxnet,zhreshold/mxnet,dmlc/mxnet,sxjscience/mxnet,zhreshold/mxnet,yajiedesign/mxnet,eric-haibin-lin/mxnet,dmlc/mxnet,eric-haibin-lin/mxnet,yajiedesign/mxnet,szha/mxnet,yajiedesign/mxnet,zhreshold/mxnet,reminisce/mxnet,yajiedesign/mxnet,leezu/mxnet,reminisce/mxnet,ForkedReposBak/mxnet,tlby/mxnet,tlby/mxnet,yajiedesign/mxnet,leezu/mxnet,ptrendx/mxnet,szha/mxnet,apache/incubator-mxnet,tlby/mxnet,ptrendx/mxnet,ptrendx/mxnet,tlby/mxnet,ptrendx/mxnet,leezu/mxnet,szha/mxnet,reminisce/mxnet,reminisce/mxnet,sxjscience/mxnet,reminisce/mxnet,ForkedReposBak/mxnet,apache/incubator-mxnet,sxjscience/mxnet,DickJC123/mxnet,szha/mxnet,sxjscience/mxnet,reminisce/mxnet,apache/incubator-mxnet,dmlc/mxnet,dmlc/mxnet,larroy/mxnet,reminisce/mxnet,ptrendx/mxnet,eric-haibin-lin/mxnet,leezu/mxnet,yajiedesign/mxnet,szha/mxnet,DickJC123/mxnet,tlby/mxnet,leezu/mxnet,sxjscience/mxnet,ptrendx/mxnet,DickJC123/mxnet,szha/mxnet,yajiedesign/mxnet,ForkedReposBak/mxnet,ptrendx/mxnet,eric-haibin-lin/mxnet,leezu/mxnet,dmlc/mxnet,sxjscience/mxnet,dmlc/mxnet,sxjscience/mxnet,eric-haibin-lin/mxnet,szha/mxnet,tlby/mxnet,zhreshold/mxnet,reminisce/mxnet,zhreshold/mxnet,tlby/mxnet,ForkedReposBak/mxnet,ptrendx/mxnet,zhreshold/mxnet,szha/mxnet,sxjscience/mxnet,dmlc/mxnet,yajiedesign/mxnet,szha/mxnet,reminisce/mxnet,larroy/mxnet,eric-haibin-lin/mxnet,ForkedReposBak/mxnet,leezu/mxnet,eric-haibin-lin/mxnet,tlby/mxnet,larroy/mxnet,larroy/mxnet,sxjscience/mxnet,reminisce/mxnet,larroy/mxnet,yajiedesign/mxnet,leezu/mxnet,dmlc/mxnet