修复文件上传bug

app/controller/Upload.php

@@ -82,7 +82,7 @@ class Upload extends Base {
 
 	public function upload(){
 		$type = $this->request->param('type');
-		$upload_type = (false !== strpos("image", $type)) ? "image" : 'file';
+		$upload_type = (false !== strpos($type, "image")) ? "image" : 'file';
 		$config      = $this->$upload_type();
 		// 获取表单上传文件 例如上传了001.jpg
 		$file =  $this->request->file('file');