message: Fix proc execution on Windows
diff: @@ -94,9 +94,13 @@ export function execute(command: string,
  options?: proc.SpawnOptions): Subprocess {
  let child: proc.ChildProcess | null = null;
  const result = new Promise<ExecutionResult>((resolve, reject) => {
  + if (process.platform != 'win32') {
  // We wrap things in `stdbuf` to disable output buffering.
  const subargs = [ '-o', '0', '-e', '0' ].concat([ command ], args);
  child = proc.spawn('stdbuf', subargs, options);
  + } else {
  + child = proc.spawn(command, args, options);
  + }
  child.on('error', (err) => { reject(err); });
  let stdout_acc = '';
  let line_acc = '';
  