ensure tmp folder is always removed no matter how process exits

Author: yyx990803

bin/vue-init

@@ -150,9 +150,11 @@ function downloadAndGenerate (template) {
   spinner.start()
   download(template, tmp, { clone: clone }, function (err) {
     spinner.stop()
+    process.on('exit', function () {
+      rm(tmp)
+    })
     if (err) logger.fatal('Failed to download repo ' + template + ': ' + err.message.trim())
     generate(name, tmp, to, function (err) {
-      rm(tmp)
       if (err) logger.fatal(err)
       console.log()
       logger.success('Generated "%s".', name)