[gvfs/nfs] Update comment

[Ross Lagerwall <rossl src gnome org>]

commit 3343120e86614b341295cca3bd83db1b9453d5b5
Author: Ross Lagerwall <rosslagerwall gmail com>
Date:   Mon Feb 2 23:00:24 2015 +0000

    Update comment

 daemon/gvfsbackendnfs.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/daemon/gvfsbackendnfs.c b/daemon/gvfsbackendnfs.c
index 4a52043..255f26c 100644
--- a/daemon/gvfsbackendnfs.c
+++ b/daemon/gvfsbackendnfs.c
@@ -863,7 +863,8 @@ copy_file (struct nfs_context *ctx,
 }
 
 /* The replace code that follows is relatively straightforward but difficult to
- * read due to its asynchronous nature.
+ * read due to its asynchronous nature.  It closely follows the replace
+ * implementation for local files in GIO, but in an async fashion.
  * Firstly, the file is opened with O_EXCL.  If this fails, the file exists.
  * Some checks on the existing file are made.  If possible, a temporary file is
  * opened and renamed over the existing file on close.  If a backup is needed,