Create a lib from our migrations helper

[anbraten]

It would be nice to use the migrations helpers from Woodpecker in other projects (exp Gitea) using xorm as well.

https://github.com/woodpecker-ci/woodpecker/blob/master/server/store/datastore/migration/common.go

[6543]

https://github.com/go-gitea/gitea/blob/main/models/migrations/migrations.go#L522-L1016 is also worth a look

[qwerty287]

And the migration handling itself probably too.

[anbraten]

Got pointed to https://github.com/techknowlogick/xormigrate