Shaft/ONEZ command - output is 2-zone solution about cfast HOT 2 CLOSED

CFAST does model the problem as two zones, then makes nearly 100 % of the 
volume the upper layer while 
keeping the mass and energy balance consistent.  While it does technically 
still have a lower layer, it's very small.  
That said, we can modify the output files to only include the upper layer data. 
 This is easy for the printed output 
file and somewhat harder for the spreadsheet files.

Resolved with revision 31.  Removed printout for lower layer temperature and 
species, interface height for compartments that are shafts.