code: function runExec(container) {
  
    var options = {
      Cmd: ['bash', '-c', 'echo test $VAR'],
      Env: ['VAR=ttslkfjsdalkfj'],
      AttachStdout: true,
      AttachStderr: true
    };
  
    container.exec(options, function(err, exec) {
      if (err) return;
      exec.start(function(err, stream) {
        if (err) return;
  
        container.modem.demuxStream(stream, process.stdout, process.stderr);
  
        exec.inspect(function(err, data) {
          if (err) return;
          console.log(data);
        });
      });
    });
  }
docs: Get env list from running container
  @param container