pgsql: Repair possible failure to update hint bits back to disk, per

Log Message:
-----------
Repair possible failure to update hint bits back to disk, per
http://archives.postgresql.org/pgsql-hackers/2004-10/msg00464.php.
This fix is intended to be permanent: it moves the responsibility for
calling SetBufferCommitInfoNeedsSave() into the tqual.c routines,
eliminating the requirement for callers to test whether t_infomask changed.
Also, tighten validity checking on buffer IDs in bufmgr.c --- several
routines were paranoid about out-of-range shared buffer numbers but not
about out-of-range local ones, which seems a tad pointless.

Modified Files:
--------------
    pgsql/contrib/pgstattuple:
        pgstattuple.c (r1.16 -> r1.17)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/pgstattuple/pgstattuple.c.diff?r1=1.16&r2=1.17)
    pgsql/src/backend/access/heap:
        heapam.c (r1.178 -> r1.179)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/heap/heapam.c.diff?r1=1.178&r2=1.179)
    pgsql/src/backend/access/index:
        indexam.c (r1.75 -> r1.76)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/index/indexam.c.diff?r1=1.75&r2=1.76)
    pgsql/src/backend/access/nbtree:
        nbtinsert.c (r1.116 -> r1.117)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/nbtree/nbtinsert.c.diff?r1=1.116&r2=1.117)
    pgsql/src/backend/catalog:
        index.c (r1.240 -> r1.241)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/index.c.diff?r1=1.240&r2=1.241)
    pgsql/src/backend/commands:
        vacuum.c (r1.294 -> r1.295)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/vacuum.c.diff?r1=1.294&r2=1.295)
        vacuumlazy.c (r1.46 -> r1.47)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/vacuumlazy.c.diff?r1=1.46&r2=1.47)
    pgsql/src/backend/storage/buffer:
        bufmgr.c (r1.177 -> r1.178)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/storage/buffer/bufmgr.c.diff?r1=1.177&r2=1.178)
    pgsql/src/backend/utils/adt:
        ri_triggers.c (r1.73 -> r1.74)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/ri_triggers.c.diff?r1=1.73&r2=1.74)
    pgsql/src/backend/utils/time:
        tqual.c (r1.79 -> r1.80)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/time/tqual.c.diff?r1=1.79&r2=1.80)
    pgsql/src/include/access:
        valid.h (r1.34 -> r1.35)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/access/valid.h.diff?r1=1.34&r2=1.35)
    pgsql/src/include/storage:
        bufmgr.h (r1.86 -> r1.87)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/storage/bufmgr.h.diff?r1=1.86&r2=1.87)
    pgsql/src/include/utils:
        tqual.h (r1.53 -> r1.54)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/utils/tqual.h.diff?r1=1.53&r2=1.54)