pgsql: Track walsender state in shared memory and expose in pg_stat_rep

Track walsender state in shared memory and expose in pg_stat_replication

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=4c8e20f815cbdf043d6d27906fd85ae50c9e4870

Modified Files
--------------
doc/src/sgml/monitoring.sgml         |    4 +-
src/backend/catalog/system_views.sql |    1 +
src/backend/replication/basebackup.c |    3 ++
src/backend/replication/walsender.c  |   49 ++++++++++++++++++++++++++++++++-
src/include/catalog/catversion.h     |    2 +-
src/include/catalog/pg_proc.h        |    2 +-
src/include/replication/walsender.h  |   11 +++++++
7 files changed, 66 insertions(+), 6 deletions(-)