async function parseCsv (data) {
  return new Promise(resolve => {
    data = data.map((row) => {
      return Object.keys(row).sort().map(key => parseFloat(row[key]));
    });
    resolve(data);
  });
}
@param {Array<Object>} data Downloaded data.

@returns {Promise.Array<number[]>} Resolves to data with values parsed as
    floats.