pgsql: Fix escaping in generated recovery.conf file.

Fix escaping in generated recovery.conf file.

In the primary_conninfo line that "pg_basebackup -R" generates, single
quotes in parameter values need to be escaped into \\'; the libpq parser
requires the quotes to be escaped into \', and recovery.conf parser requires
the \ to be escaped into \\.

Also, don't quote parameter values unnecessarily, to make the connection
string prettier. Most options in a libpq connection string don't need
quoting.

Reported by Hari Babu, closer analysis by Zoltan Boszormenyi, although I
didn't use his patch.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/30b5ede7157e34e77c7914b8ecfd55aa8da6edc3

Modified Files
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src/bin/pg_basebackup/pg_basebackup.c | 101 +++++++++++++++++++++++++++++----
1 files changed, 89 insertions(+), 12 deletions(-)