* change docs from 1.x to main
* bump version
* update readme status info and highlights
* revert version change
* fix dead links
* fix script
* fix docs
* fix building status
* fix md lint error
* upgrade to ubuntu20.04 for github ci
* Revert "upgrade to ubuntu20.04 for github ci"
This reverts commit 9c598f4857.
* update codebase md files
* upgrade to ubuntu20.04 for github ci
* fix
* fix requirements
* fix
* fix ci
* bump version
* fix
* fix pplnn torchscript
* fix building status
* fix ncnn
* fix
* remove circileci hold
* fix pytorch image