🚀 go-pugleaf

I still think that random_permutation/2 should do the same think as
permutation/2, but return solutions in random order. This is also
how I specified random_perm/2 in my recent posting.

Besides, I think there is a more natural solutions to random clause
selection, which avoids indexing clauses:

	random_solve(true).
	random_solve((A,B)):- random_solve(A), random_solve(B).
	random_solve(A):- findall((A:-B),rule(A,B),RuleList),
			  random_perm(RuleList,RulePerm),
			 		   !,
			  member((A:-B),RulePerm),
			 		   random_solve(B).

Note that this is no implementation version.

thom