code: function discernFormat(filePath) {
    var ext = extname(filePath);
    if (ext === '') return false;
  
    // Chop '.' off extension returned by extname
    var formatName = ext.slice(1);
    return formatName;
  }
docs: Given a `filePath` return the file's extension. Used internally by {@link discernParser} and {@link discernFileFormatter}. Returns `false` for files without an extension, including dotfiles
  
  @function discernFormat
  @param {String} filePath Input file path
  @returns {String} The file's extension
  
  @example
  var format = io.discernFormat('path/to/data.csv')
  console.log(format) // 'csv'
  
  @example
  var format = io.discernFormat('path/to/.dotfile')
  console.log(format) // false