Fixed bugs list:

Fixed bugs list:

1) Several places with comparation of int and unsigned (fails,
if unsigned equal zero);

2) All windows not started from top of the screen refreshes
incorrectly (I mean here not visual looking, but
minimize-output-chars refresh technique).
UCB often forget to add win->begy to index;

3) Uncommented #ifdef DEBUG in refresh dumps core, address
beyond array ranges;

4) clsp in refresh.c (number of last space on curscr) calculates
incorrectly, so CE don't work properly;

5) Litlle prototype cleanup.