* fix failed tests in yingchun gived list

* add unittests into static_mode_white_list

* add enable static

* fix dist unittest

* skip test_sigmoid_focal_loss_op & add gym

* revert no need skip unittests

* remove gym

just skip case of distribute on windows

* add to_readable_code method, test=develop

* polish doc details, test=develop

* polish doc note, test=develop

* fix unittest error, test=develop

* fix coverage, test=develop

* add print test, test=develop

* add print param, test=develop

* hidden to_readable_code api, test=develop

* remove original tool methods, test=develop

* remove old api using code, test=develop