directory should have mod-time

client.go

@@ -90,7 +90,7 @@ func (c *Client) ReadDir(path string) ([]os.FileInfo, error) {
 			if p.Type.Local == "collection" {
 				f.path += "/"
 				f.size = 0
-				f.modified = time.Unix(0, 0)
+				f.modified = parseModified(&p.Modified)
 				f.isdir = true
 			} else {
 				f.size = parseInt64(&p.Size)