filer: Add attr.mode in query string
filer: Add attr.mode in query string

Signed-off-by: Lei Liu <18becd4d236b88df68cabc820bf5fe5c57d779a7@gmail.com>

chrislusf/seaweedfs,chrislusf/seaweedfs,chrislusf/seaweedfs,chrislusf/seaweedfs