* add cn doc of unbind API

* add paddle.nn.functional.interpolate doc
test=document_preview

* modified doc tree

* fix example,add annotation

* change order

fix the diff of sample code in chinese doc with english doc

Add the Chinese doc for the api of equal, linspace, matmul

* Implement the chinese documentation of inverse.

* Add the documentation of error type.

* Remove the example of static graph.

add the doc of chinese document randint

* test=develop, add addmm doc

* add addmm doc

* test=develop, add addmm doc

Add paddle.framework.manual_seed ch doc

* add doc of L1Loss, test=develop

* refine doc, test=develop

* add cn doc of trace API

* add cn doc of diag_embed API

* add bmm arange api_doc test=develop

* Add randperm cn doc, test=develop, test=document_preview

* add doc for kron op, test=document_preview

* add support for integer types, test=document_preview

* add cross, roll, index_select, nonzero api_cn

* test=document, add cross,index_select,nonzero,roll cn doc

* test=document, bug fix for syntax error

* add paddle.sin, sqrt, tanh, atan cn doc to fluid docs

test=develop

* Add Chinese document of API: randn

paddle.add doc for elementwise_add operator 
paddle.div doc for elementwise_div operator 

fix chinese doc of gradient_clip 

add the the mul and pow api to the fluid tensor doc 

* add cn doc for dot and logsumexp

add the chinese doc of paddle.norm and the preview doc