pgsql: Mark contrib's GiST and GIN opclass support functions as STRICT,

Log Message:
-----------
Mark contrib's GiST and GIN opclass support functions as STRICT, for safety.
(Note: GiST penalty functions could possibly be non-strict, but none are at
present.)

Modified Files:
--------------
    pgsql/contrib/btree_gist:
        btree_gist.sql.in (r1.20 -> r1.21)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/contrib/btree_gist/btree_gist.sql.in?r1=1.20&r2=1.21)
    pgsql/contrib/cube:
        cube.sql.in (r1.24 -> r1.25)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/contrib/cube/cube.sql.in?r1=1.24&r2=1.25)
    pgsql/contrib/hstore:
        hstore.sql.in (r1.10 -> r1.11)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/contrib/hstore/hstore.sql.in?r1=1.10&r2=1.11)
    pgsql/contrib/intarray:
        _int.sql.in (r1.31 -> r1.32)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/contrib/intarray/_int.sql.in?r1=1.31&r2=1.32)
    pgsql/contrib/ltree:
        ltree.sql.in (r1.17 -> r1.18)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/contrib/ltree/ltree.sql.in?r1=1.17&r2=1.18)
    pgsql/contrib/pg_trgm:
        pg_trgm.sql.in (r1.9 -> r1.10)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/contrib/pg_trgm/pg_trgm.sql.in?r1=1.9&r2=1.10)
    pgsql/contrib/seg:
        seg.sql.in (r1.18 -> r1.19)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/contrib/seg/seg.sql.in?r1=1.18&r2=1.19)