* add black list and white list support for migrating repositories
* fix fmt
* fix lint
* fix vendor
* fix modules.txt
* clean diff
* specify log message
* use blocklist/allowlist
* allways use lowercase to match url
* Apply allow/block
* Settings: use existing "migrations" section
* convert domains lower case
* dont store unused value
* Block private addresses for migration by default
* fix lint
* use proposed-upstream func to detect private IP addr
* a nit
* add own error for blocked migration, add tests, imprufe api
* fix test
* fix-if-localhost-is-ipv4
* rename error & error message
* rename setting options
* Apply suggestions from code review
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: zeripath <art27@cantab.net>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>
