Merge pull request #2 from gyeongchan-yun/master

Fix 'Run DBS' section in README.md

Update dbs.py

Create README.md

Create README.md

try to implement a NLP example

fix bugs

remove debugging print

replace batchnorm layer to groupnorm layer to maintain parameter consistency between different workers

Merge branch 'master' of https://github.com/Soptq/Dynamic_Batch-Size_DistributedDNN

update algorithm based on the paper

implemented one cycle policy, weighted ssgd and statistic data outputing

Update README.md

update README.md

fix a crash when output_dir folder does not exists