add select/3 build-in predicate

[s-webber]

Attempts to unify the third argument with the result of removing one instance of first argument from the list represented by the second argument.

Examples:

?- select(X,[h,e,l,l,o],Z).
X = h,
Z = [e, l, l, o] ;
X = e,
Z = [h, l, l, o] ;
X = l,
Z = [h, e, l, o] ;
X = l,
Z = [h, e, l, o] ;
X = o,
Z = [h, e, l, l] ;

?- select(l,[h,e,l,l,o],Z).
Z = [h, e, l, o] ;
Z = [h, e, l, o] ;
false.

?- select(l,[h,e,l,l,o],[h,e,l,o]).
true ;
true ;
false.

?- select(p(a,B),[p(X,q), p(a,X)],Z).
B = q,
X = a,
Z = [p(a, a)] ;
B = X,
Z = [p(X, q)] ;
false.