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

fix program_desc constructor

* Optimize CRF decoding with AVX/AVX2 instruction

* Enable the AVX2 flags for compiling

* Clean the code and decrease the count of multiply calculation

* Add the support of AVX512 instruction to optimize CRF Decoding

* Clean the code

* Enable the AVX512f flags for compiling

* Clean the code for the invaluable switch

* Fixed the issue to check AVX512F status

* Clean the code

* Add some explanation of the key points