relationEntry -> targetEntity parts

[alexduryee]

The mapping from relationEntry to targetEntity is a bit odd - if there are multiple relationEntry elements (a la the Frankenstein), then they all get put into s of a single targetEntity.  I'm not fully clear on how multiple relationEntry elements were used (e.g. one-to-many relationships?), but it strikes me as something that should be split into multiple targetEntity elements.

[fordmadox]

targetEntity can only occur once in the current version of the schema, based on the Relations paper. In all of the real-world EAC 1 files that I've seen, though, I haven't stumbled across a single relation that used multiple relationEntry elements (the ones that I have seen so far included different name parts in relationEntry for the same entity, but not different entities). That said, it would be good to get a lot more feedback about the changes to the relations section during the call for comments.

@alexduryee: do you have any example relations that could demonstrate a use case for multiple targetEntity elements? I've thought of one, but haven't tried to encode those yet.

[kerstarno]

Additional thought: this might also be something to have a closer look at in the context of EAD. As I haven't seen that many real world examples of EAD3 yet that would be using <relations> I can't say for sure, but maybe the use of 1:n relationships would be more common in that context? E.g. if we were to use <relations> to point to related and/or separated material instead of using <relatedmaterial> and <separatedmaterial> respectively?