pgsql: Change pg_last_xlog_receive_location() not to move backwards. Th

Change pg_last_xlog_receive_location() not to move backwards. That makes
it a lot more useful for determining which standby is most up-to-date,
for example. There was long discussions on whether overwriting existing
existing WAL makes sense to begin with, and whether we should do some more
extensive variable renaming, but this change nevertheless seems quite
uncontroversial.

Fujii Masao, reviewed by Jeff Janes, Robert Haas, Stephen Frost.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/6eba5a7c57d1d61f46b6966026bf7bc07f8e087c

Modified Files
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doc/src/sgml/func.sgml | 6 ++----
src/backend/replication/walreceiver.c | 9 ++++++---
src/backend/replication/walreceiverfuncs.c | 13 +++++++++++--
src/include/replication/walreceiver.h | 14 ++++++++++----
4 files changed, 29 insertions(+), 13 deletions(-)