pgsql: Expose waitforarchive option through pg_stop_backup()

Expose waitforarchive option through pg_stop_backup()

Internally, we have supported the option to either wait for all of the
WAL associated with a backup to be archived, or to return immediately.
This option is useful to users of pg_stop_backup() as well, when they
are reading the stop backup record position and checking that the WAL
they need has been archived independently.

This patch adds an additional, optional, argument to pg_stop_backup()
which allows the user to indicate if they wish to wait for the WAL to be
archived or not. The default matches current behavior, which is to
wait.

Author: David Steele, with some minor changes, doc updates by me.
Reviewed by: Takayuki Tsunakawa, Fujii Masao
Discussion: https://postgr.es/m/758e3fd1-45b4-5e28-75cd-e9e7f93a4c02@pgmasters.net

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/017e4f2588a7fc6f2d1fbb6fff8afa1ff6e31f2b

Modified Files
--------------
doc/src/sgml/backup.sgml | 13 ++++++++++++-
doc/src/sgml/func.sgml | 10 ++++++++--
src/backend/access/transam/xlog.c | 3 ++-
src/backend/access/transam/xlogfuncs.c | 12 ++++++++++--
src/backend/catalog/system_views.sql | 8 +++++++-
src/include/catalog/catversion.h | 2 +-
src/include/catalog/pg_proc.h | 2 +-
7 files changed, 41 insertions(+), 9 deletions(-)