225d65268d
As I mentioned [here](https://kolaente.dev/vikunja/api/pulls/1442#issuecomment-55215), this is mainly a cleanup of @zewaren 's original [PR](https://kolaente.dev/vikunja/api/pulls/1442). It adds support for the `RELATED-TO` property in CalDAV's `VTODO` and the `RELTYPE=PARENT` and `RELTYPE=CHILD` relationships. In other words, it allows for `ParentTask->SubTask` relations to be handled supported through CalDAV. In addition to the included tests, this has been tested by both @zewaren & myself with DAVx5 & Tasks (Android) and it's been working great. Resolves https://kolaente.dev/vikunja/api/issues/1345 Co-authored-by: Miguel A. Arroyo <miguel@codeheads.dev> Co-authored-by: Erwan Martin <public@fzwte.net> Reviewed-on: https://kolaente.dev/vikunja/api/pulls/1634 Reviewed-by: konrad <k@knt.li> Co-authored-by: Miguel Arroyo <mayanez@noreply.kolaente.de> Co-committed-by: Miguel Arroyo <mayanez@noreply.kolaente.de>