Fix windows test problems.

Test files have been modified in order to respect the flake8 style.

Opt fix

Cnmem threashold, comment, don't call dnn_version and optimization registration.

Pass -rpath to linker only, not to compiler

Bilinear interpolation

Opt

Fix problems for release

Fix docgen fails due to GPU not available

keep stack trace in optimizations of nnet folder

Fix test that fails on the buildbot

cnmem=1, default to 0.95 as otherwise, there is problems by default. It will make smaller extra alloc by default if needed. We do this if cnmem > 0.99 to prevent rounding problems and allow user to start as the old way.

(#4196) increase the tolerance of test_gc_never_pickles

Kmap

Fix typo in docs