(svn r5714) Backport from branches/TGP (r5701 and r5711)

-Fix: < > boxes in patch-settings didn't grey out when they hit the limit of their range
 -Codechange: while at it, prettyfied DrawArrowButtons() a bit
 -Fix: < > boxes in industry production window (when cheat enabled) had a minor glitch

misc_gui.c

@@ -1776,7 +1776,7 @@ static void CheatsWndProc(Window *w, WindowEvent *e)
 				char buf[512];
 
 				/* Draw [<][>] boxes for settings of an integer-type */
-				DrawArrowButtons(x + 20, y, 3, clk - (i * 2), true);
+				DrawArrowButtons(x + 20, y, 3, clk - (i * 2), true, true);
 
 				switch (ce->str) {
 				/* Display date for change date cheat */