Bar cursor in bidirectional text

[Eli Zaretskii]

I committed today revno 101130 (fixed later in revno 101131) that
causes the bar cursor to be positioned correctly on right-to-left
characters.  I did that for X and w32, but not for NS, since the
relevant code in nsterm.m is slightly different and uses APIs whose
semantics I don't understand well enough.

Could someone who has access to NS please fix nsterm.m in the manner
similar to what I did for X and w32?  The changes should be in the
ns_draw_window_cursor function and affect the code under `case BAR_CURSOR'.

TIA