pgsql: Track last time for statistics reset on databases and bgwriter

Track last time for statistics reset on databases and bgwriter

Tracks one counter for each database, which is reset whenever
the statistics for any individual object inside the database is
reset, and one counter for the background writer.

Tomas Vondra, reviewed by Greg Smith

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/4c468b37a281941afd3bf61c782b20def8c17047

Modified Files
--------------
doc/src/sgml/monitoring.sgml | 29 ++++++++++++++++++++++++++---
src/backend/catalog/system_views.sql | 6 ++++--
src/backend/postmaster/pgstat.c | 13 +++++++++++++
src/backend/utils/adt/pgstatfuncs.c | 26 ++++++++++++++++++++++++++
src/include/catalog/catversion.h | 2 +-
src/include/catalog/pg_proc.h | 4 ++++
src/include/pgstat.h | 4 +++-
src/test/regress/expected/rules.out | 4 ++--
8 files changed, 79 insertions(+), 9 deletions(-)