64bit paflof with lots of gnuisms

[Stefan Reinauer]

Hi there,

I played around with paflof on 64bit platforms. 
As we make heavy use of GNUisms, I got it working using some more.
I'll attach 2 patches, one cleans up 64bit compile warnings for
the fprintf stuff (cosmetic), the other fixes the double cell issue.
Unfortunately it does not compile on 32bit platforms without the ugly
#ifdef constructs. The error messages are "no data type for mode `TI'"
I am not sure whether this is a gcc bug or rather an error in my
thoughts. Any comments?

See you,
   Stefan