Adding documentation for the operators: lod_tensor_to_array , array_to_lod_tensor, create_array, increment (#6807)
Adding documentation for the operators: lod_tensor_to_array , array_to_lod_tensor, create_array, increment (#6807)

* Adding operator assignment

* Adding a prototype for documentation in layers

* small update to re-run Travis

* Removing file from another PR

* Small typo

* Adding documentation for the operators: lod_tensor_to_array , array_to_lod_tensor, create_array, increment

* Fixing indentation issue

* Fixed datatype of input variables

chengduoZH/Paddle,lcy-seso/Paddle,lcy-seso/Paddle,putcn/Paddle,luotao1/Paddle,lcy-seso/Paddle,reyoung/Paddle,reyoung/Paddle,QiJune/Paddle,Canpio/Paddle,pkuyym/Paddle,pkuyym/Paddle,putcn/Paddle,putcn/Paddle,PaddlePaddle/Paddle,PaddlePaddle/Paddle,baidu/Paddle,lcy-seso/Paddle,PaddlePaddle/Paddle,Canpio/Paddle,pkuyym/Paddle,putcn/Paddle,pkuyym/Paddle,Canpio/Paddle,QiJune/Paddle,jacquesqiao/Paddle,Canpio/Paddle,tensor-tang/Paddle,putcn/Paddle,jacquesqiao/Paddle,Canpio/Paddle,luotao1/Paddle,luotao1/Paddle,baidu/Paddle,chengduoZH/Paddle,jacquesqiao/Paddle,jacquesqiao/Paddle,jacquesqiao/Paddle,PaddlePaddle/Paddle,PaddlePaddle/Paddle,tensor-tang/Paddle,jacquesqiao/Paddle,lcy-seso/Paddle,luotao1/Paddle,baidu/Paddle,baidu/Paddle,reyoung/Paddle,QiJune/Paddle,luotao1/Paddle,reyoung/Paddle,tensor-tang/Paddle,pkuyym/Paddle,lcy-seso/Paddle,PaddlePaddle/Paddle,Canpio/Paddle,QiJune/Paddle,QiJune/Paddle,luotao1/Paddle,pkuyym/Paddle,reyoung/Paddle,Canpio/Paddle,chengduoZH/Paddle,Canpio/Paddle,baidu/Paddle,chengduoZH/Paddle,luotao1/Paddle,tensor-tang/Paddle,putcn/Paddle,QiJune/Paddle,tensor-tang/Paddle,PaddlePaddle/Paddle,chengduoZH/Paddle,reyoung/Paddle