Regex for version of metadatasets

[sosna]

The regex for version property defined in the metadataset schema is the following: ^(0|[1-9]\d*).(0|[1-9]\d*).(0|[1-9]\d*)(?:-((?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-])(?:.(?:0|[1-9]\d|\d*[a-zA-Z-][0-9a-zA-Z-]))))?$

This imposes semantic versioning, i.e. 1.0 will be rejected as invalid.

However, unless I'm mistaken, while SDMX recommends semantic versioning, it does not imposes it and the old version numbers (e.g. 1.0, 2.1, etc.) should still work.