Bug on delete RELAXED in ReLinkListContainer

[SusieGoebel]

Please add an error to show the bug, then solve it - we are soo test-driven ;)

Comment was:

1. When checking why we could leave out the delete method in re-tree-list and re-link-list-container.ts I discovered a bug when calling delete with RELAXED mode on a ReLinkListContainer, but this has nothing to do with this pull request though but should be fixed in another issue

Originally posted by @Noah1891 in #32 (review)