packaging: ignore temp build directories (bytedance#319)

- ignore temporary build directories in packaging.
- check for existence of 3rdparty/ps-lite

Signed-off-by: Yulu Jia <yulu.jia@bytedance.com>

Use true divide (bytedance#306)

* torch: use tensor.true_divide()

in the torch extension, for pytorch >= 1.5.0 use tensor.true_divide() (i.e. floating point
divide) instead of tensor.div_() (i.e. integer divide) to average gradients.

Signed-off-by: Yulu Jia <yulu.jia@bytedance.com>

bump version number to 0.2.5 (bytedance#305)

bump version number to 0.2.5

Signed-off-by: Yulu Jia <yulu.jia@bytedance.com>

build: bump up version number to 0.2.4

bump up version number to 0.2.4

Signed-off-by: Yulu Jia <yulu.jia@bytedance.com>

build: fix classifiers

fix classifiers

Signed-off-by: Yulu Jia <yulu.jia@bytedance.com>

setup & docker: update framework and fix compile (bytedance#212)

* setup: handle cxx flag

* automatically add cuda lib for mxnet

* fix softlink location

* fix os path

* fix ld_library_path

* fix cuda default path

* refactor dockerfilie

* set proper nccl version

* add torchvision

* fix setup and use tf 1.15 for dockerfile

* improve handling of libcuda.so.1

release: v0.2.0 (bytedance#206)

* fix manifest.in

* remove tools dir

* __version__.py: 0.2.0

* update readme

* fix docs

* fix best-practice.md

* readme: nccl path

* readme: improve

* readme: improve

* add changelog.rst

* fix changelog

* readme: add pypi badge and news

* improve readme and changelog

Tag for release 0.1.0