code: function get(attr) {
            var val = dotty.get(attrs, attr);
            if (val === undefined) {
              this.emit('undefined',
                'WARNING: Undefined environment variable: ' + attr, attr);
            }
            return val;
          }
docs: Return the value of the attribute requested.
  @param  {String} attr The name of the attribute to return.
  @return {Any} The value of the requested attribute.