Improve AQL to simplifying the querying of terms

[damoca (David Moner)]

@matijap

In our case not even to all LOCATABLE.name but only to ELEMENT.name, and within that only to ELEMENT.name.mappings. (We might consider including ELEMENT.name.defining_code in the future though.)

Following this, I would be very careful when adding syntactic sugar to AQL. Not only because you need to have a very clear definition of it to avoid different interpretations and implementations, but more importantly, if we add syntactic sugar that it is only applicable to an openEHR reference model we would be deviating from the purpose of AQL (ARCHETYPE Query Language) and end with an OpenEHR Query Language. This would mean that the specification could not be valid for other reference models or even with the openEHR RM itself if it evolves in the following 10, 20, 30 years (future-proof, you know).