chore(segments): support for custom z-segments added

[evvo]

Support for custom z-segments that are not part of the HL7 specs

[Loksly]

Hi @evvo,

I've been thinking about this MR and I think it's good to support this Z custom segments, but I think they should have a description of what fields are expected. Instead of ignoring this segments, should it be a way to load more segments descriptions? what do you think?

[evvo]

Hello @Loksly ,

Unfortunately, from what I understand, we cannot predict what kind of fields these segments will contain, as they are custom and might have different fields in different implementations:

https://lyniate.com/resources/hl7-z-segments/

A Z-segment is a message segment that is defined locally and that is not part of the HL7 standard. 
Z-segments are part of the reason why the HL7 standard is considered a “flexible” standard

To my understanding, these Z-segments will contain custom information that is not part of the HL7 standard, but that can be helpful to be included in the HL7 file (for example, custom patient data).