* update loss.py in nn.functional and nn.layer module

* update nn.Pad1D and 2D,3D class in common.py

* add code copy from function anchor for cn docs code alignemnt

* update pad class in common.py

* update common.py in functional and layer model

* fix format issue

* update format issue

* update pad;test=document_fix

* update NLLLoss;test=document_fix
Co-authored-by: NLigoml <39876205+Ligoml@users.noreply.github.com>