Log Message:
-----------
Improve page split in rtree emulation. Now if splitted result has
big misalignement, then it tries to split page basing on distribution
of boxe's centers.
Per report from Dolafi, Tom <dolafit(at)janelia(dot)hhmi(dot)org>
Backpatch is needed, change doesn't affect on-disk storage.
Modified Files:
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pgsql/src/backend/access/gist:
gistproc.c (r1.10 -> r1.11)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gist/gistproc.c?r1=1.10&r2=1.11)