Fix #1383: "Save with Sudo" rewrite (#1424)

* Rewrite save with sudo (Fixes #1383)

* Combine overrideFile & overrideFileAsRoot into 1 function

internal/buffer/serialize.go

@@ -39,7 +39,7 @@ func (b *Buffer) Serialize() error {
 			b.ModTime,
 		})
 		return err
-	})
+	}, false)
 }
 
 func (b *Buffer) Unserialize() error {