Bidirectional OO-LD <-> AAS submodel converter

[SimonStier]

Convert between OO-LD schemas and Asset Administration Shell submodel templates.

Spec-side sibling: OO-LD/oold-schema#119 (generating OO-LD schemas from an existing source model).

cc @Kirankumaraswamy @durmaz07

Mapping

• Submodel and SubmodelElementCollection to object schemas; Property, MultiLanguageProperty and Range to typed schema properties
• semanticId to the IRI carried in the OO-LD @context
• Cardinality and value types to required, arrays and JSON Schema types
• Quantity-like SubmodelElements to the OO-LD quantity value representation, see QuantityValue as a base building block: one syntax, consensus @context, x-oold-context synonyms (worked example) oold-schema#107

Open questions

• Which AAS metamodel version and which serialisation to target (JSON, XML, RDF)
• Compliance with published IDTA submodel templates: the converter should be able to consume one unchanged
• Relation to the SAMM converter (Bidirectional OO-LD <-> SAMM converter #111). AAS submodel templates can be generated from SAMM, so this could chain through SAMM or be implemented independently. Left open for now