Fixup the dos makefile and check it out on dos.

Remove opening lines gnuchess doesn't play well.

The hint problem.  If the hint is a promotion move easy mode
doesnt work right. It is currently bypassed in this case.
Search doesn't save the fact its a promotion move in the
PV. So hint and post only show the move without the piece
being promoted to. Cannot do easy mode off, because it must
know the piece being promoted to. Somehow should save it in PV.
Also true for hashtable entries. flags are not saved they should
be.

Make the hash table include castling flags + ep flag + promotion flags.
Currently only the transposition file include any of these and
then only castling for the side to move.
