* Fix various doc, user-facing, and source comment typos Found via `codespell -q 3 -S ./options/locale,./vendor -L ba,pullrequest,pullrequests,readby`
* Make the github migration less rate limit waiting to get comment per page from repository but not per issue * Fix lint * adjust Downloader interface * Fix missed reviews * Fix test * Remove unused struct
Add support to migrate gogs: * issues * comments * labels * milestones * wiki Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com> Co-authored-by: Andrew Thornton <art27@cantab.net>