Merge pull request !3742 from liubuyu/r0.6

Merge pull request !3730 from jinyaohui/mix_presion

Merge pull request !3548 from ZPaC/r0.6-pass-attr-to-ps

Merge pull request !3733 from lvchangquan/r.06

Merge pull request !3724 from wanghua/r0.6

Merge pull request !3703 from JoyLvliang/r0.6

Merge pull request !3718 from chenzhongming/r0.6

Merge pull request !3704 from vlne-v1/amp_doc_r0.6

add mindspore.hub and change model_zoo

Merge pull request !3681 from ms_yan/vgg_r0.6

Merge pull request !3685 from wanghua/r0.6

Merge pull request !3682 from panfengfeng/googlenet-gpu_support

Merge pull request !3689 from kisnwang/r0.6-fix-cpu-multi-graph-memory-error

Merge pull request !3628 from gukecai/log

Merge pull request !3673 from hexia/fix_input_check_r0.6

Merge pull request !3683 from shenwei41/r0.6

Merge pull request !3666 from hanjun996/r0.6

Merge pull request !3596 from wangqiuliang/fix-batchnorm-r0.6

merge the script

optimize the script

repair problem in vgg16 cifar10 version

optimize the vgg script

Merge pull request !3680 from wangnan39/lowering_value_checking_threshold_to_support_training_with_very_small_steps

Merge pull request !3649 from changzherui/mod_ver_num

Merge pull request !3677 from zhouyaqiang0/r0.6

Merge pull request !3659 from meixiaowei/r0.6

Merge pull request !3558 from guozhijian/fix_dataset_none_hung

Merge pull request !3586 from guansongsong/gss/fix_python_api_for_r0.6

Merge pull request !3584 from guansongsong/gss/fix_cache

Merge pull request !3632 from Kang/r0.6

Merge pull request !3604 from peixu_ren/r0.6