Log Message:
-----------
Fix a few typos in comments in snapmgr.c, and sort header inclusions
alphabetically.
Modified Files:
--------------
pgsql/src/backend/utils/time:
snapmgr.c (r1.2 -> r1.3)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/time/snapmgr.c?r1=1.2&r2=1.3)