[THREDDS #NCD-931813]: How to add GLOBAL attributes to an Aggregation

Yes, I agree the NcML augmentation is the way to fix this, i just need to do a 
bunch of regression testing to make sure i dont break anything. So, yes you 
will be able to use the NcML you sent, once i fix it.

In thinking about the HDF problem, I think we should report it (to who?) as a 
bug.

Ticket Details
===================
Ticket ID: NCD-931813
Department: Support THREDDS
Priority: Normal
Status: Open