pgsql: Make pg_basebackup use temporary replication slots

Make pg_basebackup use temporary replication slots

Temporary replication slots will be used by default when wal streaming
is used and no slot name is specified with -S. If a slot name is
specified, then a permanent slot with that name is used. If --no-slot is
specified, then no permanent or temporary slot will be used.

Temporary slots are only used on 10.0 and newer, of course.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/e7b020f786bf3b344f81d70aa423525fd4f44dfa

Modified Files
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doc/src/sgml/ref/pg_basebackup.sgml | 25 ++++++++++++++++
src/bin/pg_basebackup/pg_basebackup.c | 45 +++++++++++++++++++++++++++-
src/bin/pg_basebackup/pg_receivexlog.c | 3 ++
src/bin/pg_basebackup/pg_recvlogical.c | 1 +
src/bin/pg_basebackup/receivelog.c | 22 ++++++++++++--
src/bin/pg_basebackup/receivelog.h | 6 ++--
src/bin/pg_basebackup/streamutil.c | 1 -
src/bin/pg_basebackup/streamutil.h | 1 -
src/bin/pg_basebackup/t/010_pg_basebackup.pl | 5 +++-
9 files changed, 101 insertions(+), 8 deletions(-)