function compare(v1, v2) {
  if (v2 === DEV_VERSION) return v1 === DEV_VERSION ? 0 : -1;
  if (v1 === DEV_VERSION) return 1;
  if (v2 === LATEST) return v1 === LATEST ? 0 : -1;
  if (v1 === LATEST) return 1;
  return semver.compare(v1, v2);
}
Compares the given versions. Compatible with Array.sort.
@param {string} v1 The first version to compare.
@param {string} v2 The second version to compare.
@returns {number} A number indicating the relationship between the versions.