pgsql: Allow times of 24:00:00 to match rounding behavior:

Log Message:
-----------
Allow times of 24:00:00 to match rounding behavior:

regression=# select '23:59:59.9'::time(0);
time
----------
24:00:00
(1 row)

This is bad because:

regression=# select '24:00:00'::time(0);
ERROR: date/time field value out of range: "24:00:00"

The last example now works.

Modified Files:
--------------
pgsql/doc/src/sgml:
datatype.sgml (r1.160 -> r1.161)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/datatype.sgml.diff?r1=1.160&r2=1.161)
pgsql/src/backend/utils/adt:
datetime.c (r1.158 -> r1.159)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/datetime.c.diff?r1=1.158&r2=1.159)
nabstime.c (r1.143 -> r1.144)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/nabstime.c.diff?r1=1.143&r2=1.144)
pgsql/src/interfaces/ecpg/pgtypeslib:
dt_common.c (r1.30 -> r1.31)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/interfaces/ecpg/pgtypeslib/dt_common.c.diff?r1=1.30&r2=1.31)