function getIphotoVersion(desc) {
  var matches = desc.match(/\d/g);
  return matches.join('.');
}
The plugin description string contains the version number as in the form
'iPhoto 700'. This returns just the version number as a dotted string,
e.g., '7.0.0', compatible with `goog.string.compareVersions`.
@param {string} desc The version string.
@return {string} The dotted version.