speed up while_op

* doc: append PADDLE_ENFORCE rules to new_op_cn.md

* doc: polish writing

* refactor: polish doc based on advice

 fix ssa bug with batch_norm and  refine the trt

* Fuse Convolution and Eltwise Add into Conv+Bias

* Reduce bias branching at conv_mkldnn_op

* Add MKLDNN build checks for Conv Bias

* Conv-bias: check if bias input exist befor assignment

* Conv-bias: Remove Bias dim check from infershape

It was causing conv3d test to crash upon\ncalling HasInput(Bias)

* link IR graph to analysis graph

* add clean code and update

* add infer_clean_pass

* add ir_pass_manager

* support fc fuse executation

* fix ir circle

Refine  elementwise mul cpu forward

add load slice_vars in io.py

Fix python3 CI job

* add async dist tests

* update delta

* fix transformer test

* refine rmsprop transpile

* update

* fix dist seresnet

only change rpath in Release mode

Add batch norm trt converter

* Fix scatter_op python API and remove inconsistency between implementation and doc

* API spec change

* Change as review comment

Port dist_transpiler new added codes
Port ut for clone desc

fix SEGV element wise add at debug mode

Fix anakin in manylinux1

add fusion lstm 

fix some teeny mistakes

fix tensorrt compiler bug

Refactor: remove inplace parameter from squeeze and unsqueeze op