GitLab

* adding mixed precision training with Apex

* fix APEX default optimization level

* adding python version check for apex

* fix LINT errors and raise exceptions if apex not available

Allows for easily evaluating the pre-trained models in the modelzoo

* Miscellaneous improvements to the classification reference scritps

* Fix lint

* Add groups support to ResNet

* Kill BaseResNet

* Make it support multi-machine training

Making references/classification/train.py and references/classification/utils.py  compatible with python2  (#831)

* linter fixes

* linter fixes

* Initial version of classification reference training script

* Updates

* Minor updates

* Expose a few more options

* Load optimizer and lr_scheduler when resuming

Also log the learning rate

* Evaluation-only and minor improvements

Identified a bug in the reporting of the results. They need to be reduced between all processes

* Address Soumith's comment

* Fix some approximations on the evaluation metric

* Flake8