* use different structs for MigrateRepoOptions on UI and API
* Fix TokenAuth and rename UID to an understandable Name
* fix swagger doc
* simplify & mk redable
* R E F A C T O R:
migration has now internal 3 structs to store its options:
* the Options for WebUI: modules/auth/repo_form.go
* the Options for API: modules/structs/repo.go
* the option struct with after validation for internal prossessing: modules/migrations/base/options.go
* Copyright Header
* Deprecate UID - add RepoOwner
* adopt repo.go -> migrate.go
* add comment about each struct purpose
* lint
* Store original author info for migrated issues and comments
Keep original author name for displaying in Gitea interface and also
store original author user ID for potential future use in linking
accounts from old location.
* Add original_url for repo
Store the original URL for a migrated repo
Clean up migrations/tests
* fix migration
* fix golangci-lint
* make 'make revive' happy also
* Modify templates to use OriginalAuthor if set
Use the original author name in templates if it is set rather than the
user who migrated/currently owns the issues
* formatting fixes
* make generate-swagger
* Use default avatar for imported comments
* Remove no longer used IgnoreIssueAuthor option
* Add OriginalAuthorID to swagger also