Release v8.15.0 (libvips#3752)

Release v8.15.0-rc2 (libvips#3745)

Release v8.15.0-rc1 (libvips#3719)

Release v8.14.5 (libvips#3663)

Release v8.14.4 (libvips#3615)

Release v8.14.3 (libvips#3569)

Release v8.14.2 (libvips#3396)

fix jpeg autorotate for orientation 3

we were not clearing the orientation tag if width and height were
unaltered by the orientation change

see libvips#3268

thanks zhifengzhuang

make arrayjoin much faster with large arrays

arrayjoin was making a region on every input image during startup, and
repeating for each thread (!!) so large arrays could be very expensive
to join.

Instead, make input regions on demand, and computre set of required
input images rather than searching for them.

See libvips#3247

note release date for 8.14