Number of loopback devices

[Dale Amon]

Loopbacks are so damned useful that I'm certain I'll
soon run out of them, and I doubt I'm the only person
in that position, particularly with some of the 
improvements in the crypto patches making it possible
to run an all crypto system.

I note that the number is set in loop.c

	static int max_loop = 8;

and I wonder what the safe upper limit for this is, 
and if there is some reason for not making it larger
or perhaps making it a CONFIGurable item?