Added Webdav driver rename fallback

mod/filesystem/abstractions/webdavfs/webdavfs.go

@@ -105,7 +105,22 @@ func (e WebDAVFileSystem) RemoveAll(filename string) error {
 func (e WebDAVFileSystem) Rename(oldname, newname string) error {
 	oldname = filterFilepath(filepath.ToSlash(filepath.Clean(oldname)))
 	newname = filterFilepath(filepath.ToSlash(filepath.Clean(newname)))
-	return e.c.Rename(oldname, newname, true)
+	err := e.c.Rename(oldname, newname, true)
+	if err != nil {
+		//Unable to rename due to reverse proxy issue. Use Copy and Delete
+		f, err := e.c.ReadStream(oldname)
+		if err != nil {
+			return err
+		}
+
+		err = e.c.WriteStream(newname, f, 0775)
+		if err != nil {
+			return err
+		}
+		f.Close()
+		e.c.RemoveAll(oldname)
+	}
+	return nil
 }
 func (e WebDAVFileSystem) Stat(filename string) (os.FileInfo, error) {
 	filename = filterFilepath(filepath.ToSlash(filepath.Clean(filename)))