IntPairSeqPtr definition incorrect

[pqnelson]

The definition of IntPairSeqPtr appears to be incorrect. Right now, it is defined as:

  IntPairSeqPtr = ^BinIntFunc;

But it should instead be defined as:

  IntPairSeqPtr = ^IntPairSeq;

This isn't used anywhere in Mizar, which is probably why this bug hasn't been caught earlier. I only caught it by trying to unit test IntPairSeq.