fasthadd file permissions

The new fastHadd external deals correctly with file permissions, by setting them to `0664`: this allows for testing/debugging purposes (files are accessible by all users), and for correctly handling files in `DAQ2` (while in the same step, files are handled by the same user, when moved in the data flow chain, files should be handled by users in the same group).
Did you actually try this out? # is not a commend character for rpm keywords (like %define). You might want to move the comment above the define.