cleanupLabel = function cleanupLabel(label) {
  if (label.substring(0, 1) === ':') {
    return label.substr(1).trim();
  } else {
    return label.trim();
  }
}
Called by parser when a link is found. Adds the URL to the vertex data.
@param ids Comma separated list of ids
@param linkStr URL to create a link for
@param tooltip Tooltip for the clickable element