Change backup policy

1 - Reports the error to the user in a popup.
2 - Names of the backups include the timstamp instead of a number. Names have more sense and the files can be sorted by names what is also the age order.
3 - Behaviors when changing configuration improved, the number of files present on the system was not reduced when reducing the number of backups or backups deactivated.

src/Base/FileInfo.cpp

@@ -482,6 +482,9 @@ bool FileInfo::renameFile(const char* NewName)
         int code = errno;
         std::clog << "Error in renameFile: " << strerror(code) << " (" << code << ")" << std::endl;
     }
+    else {
+        FileName = NewName;
+    }
 
     return res;
 }