This defines the [even/odd]-[2...31]-parity problem family, with
or without adfs.  Because there are so many possible functions
necessary to do, for example, even-31-parity (!), the parameter
files are big and hairy.  But here's what you need to know to change
the values.

The parameter which determines even/odd is:

	eval.problem.even

The parameter which determines the value from 2...31 is:

	eval.problem.bits

However, after you change eval.problem bits, you need to
change the gp.fs.0.size (and for adfs, the gp.fs.1.size
and gp.fs.2.size) parameter immediately after it as it
describes.  This determines the function set used.