def prefix_tag(tag)
      tag = Origen::VersionString.new(tag)
      if tag.semantic?
        tag.prefixed
      else
        tag
      end
    end
def prefix_tag(tag)
      tag = Origen::VersionString.new(tag)
      if tag.semantic?
        tag.prefixed
      else
        tag
      end
    end
If the supplied tag looks like a semantic version number, then make sure it has the
 'v' prefix