GitLab

* add precommmit to check readme

* update

* fix typos

* refactor PN SA module code

* refactor PAConv op & add PAConvSAModule

* add unit test

* add PAConvCUDA SA module

* add unit test

* minor fix

* merge master

* move paconv sa modules to a new file

* rename to BasePointSAModule

* rename to PAConvCUDASAModule

* delete typing comment

* refine docs

* rename mlp_spec to mlp_channel

* fix typos in comment

* support knn query in QueryAndGroup

* add cuda implemented assign_scores op

* add unit test for paconv assign_score op

* refactor op

* add non-cuda & cuda version PAConv

* minor fix

* fix cuda-9.0 compatibility

* add weight init of paconv

* fix typos

* refactor paconv