docs: function removeLeftMargin( code ) {
    var margin = 999;
    var lines = code.split("\n");
    lines.forEach(function (line) {
      var s = line.length;
      var m = 0;
      while( m < s && line.charAt(m) == ' ' ) m++;
      margin = Math.min( m, margin );
    });
    return lines.map(function(line) {
      return line.substr( margin );
    }).join("\n");
  }