UFTP protocol version not defined consistently

[tomwetjens]

In the spec it says:
"TXT record specifying the version of the USEF specification implemented by this participant, e.g. 2015"

On https://www.usef.energy/news-events/publications/ it is called for example V1.01.

And in the XSD the Version attribute is defined as a semver in format: x.y.z.

As an implementor it's not clear what versioning scheme should be used.

[tomwetjens]

USEF website is considered out of date. There should be a Shapeshifter website (out of scope for this issue).

Semver should be leading. So update spec TXT records should be semver.
XSD is already correct.