Bidi reordering of display and overlay strings is on the trunk

[Eli Zaretskii]

I've committed to the trunk a few moments ago revision 105208 which
includes support for reordering overlay and display strings.

bidi-display-reordering is not yet set by default; I plan on doing
that in a couple of days, assuming that a few people (myself included)
who run with it all the time don't report any grave bugs or
instabilities.

If any of you set bidi-display-reordering to a non-nil value and see
some strange or unexpected behavior in the display area, please reset
the variable and try again.  Please report the effect of this with the
bug you submit (if you submit).

This commit also fixes a few long-standing bugs with bidi redisplay,
see the logs.

TIA