pgsql: pg_rewind: Allow writing recovery configuration

pg_rewind: Allow writing recovery configuration

This is provided with a new switch --write-recovery-conf and reuses the
pg_basebackup code.

Author: Paul Guo, Jimmy Yih, Ashwin Agrawal
Reviewed-by: Alexey Kondratov, Michaël Paquier, Álvaro Herrera
Discussion: https://postgr.es/m/CAEET0ZEffUkXc48pg2iqARQgGRYDiiVxDu+yYek_bTwJF+q=Uw@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/927474ce1a2498ddb617c6113a88ca61fbba161d

Modified Files
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doc/src/sgml/ref/pg_rewind.sgml | 13 +++++++++++++
src/bin/pg_rewind/Makefile      |  2 +-
src/bin/pg_rewind/libpq_fetch.c |  3 +--
src/bin/pg_rewind/pg_rewind.c   | 35 ++++++++++++++++++++++++++++++++++-
src/bin/pg_rewind/pg_rewind.h   |  9 +++++++--
5 files changed, 56 insertions(+), 6 deletions(-)