pgsql: Clean up the messy semantics (not to mention inefficiency) of

Log Message:
-----------
Clean up the messy semantics (not to mention inefficiency) of PageGetTempPage
by splitting it into three functions with better-defined behaviors.

Zdenek Kotala

Modified Files:
--------------
pgsql/src/backend/access/gin:
gindatapage.c (r1.11 -> r1.12)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gin/gindatapage.c?r1=1.11&r2=1.12)
ginentrypage.c (r1.17 -> r1.18)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gin/ginentrypage.c?r1=1.17&r2=1.18)
ginutil.c (r1.17 -> r1.18)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gin/ginutil.c?r1=1.17&r2=1.18)
ginvacuum.c (r1.24 -> r1.25)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gin/ginvacuum.c?r1=1.24&r2=1.25)
pgsql/src/backend/access/gist:
gist.c (r1.152 -> r1.153)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gist/gist.c?r1=1.152&r2=1.153)
gistvacuum.c (r1.39 -> r1.40)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gist/gistvacuum.c?r1=1.39&r2=1.40)
pgsql/src/backend/access/nbtree:
nbtinsert.c (r1.167 -> r1.168)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/nbtree/nbtinsert.c?r1=1.167&r2=1.168)
pgsql/src/backend/storage/page:
bufpage.c (r1.80 -> r1.81)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/storage/page/bufpage.c?r1=1.80&r2=1.81)
pgsql/src/include/access:
gin.h (r1.25 -> r1.26)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/access/gin.h?r1=1.25&r2=1.26)
pgsql/src/include/storage:
bufpage.h (r1.83 -> r1.84)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/storage/bufpage.h?r1=1.83&r2=1.84)