pgsql: Fix pg_dumpall to work for databases flagged as read-only.

Fix pg_dumpall to work for databases flagged as read-only.

pg_dumpall's charter is to be able to recreate a database cluster's
contents in a virgin installation, but it was failing to honor that
contract if the cluster had any ALTER DATABASE SET
default_transaction_read_only settings. By including a SET command
for the connection for each connection opened by pg_dumpall output,
errors are avoided and the source cluster is successfully
recreated.

There was discussion of whether to also set this for the connection
applying pg_dump output, but it was felt that it was both less
appropriate in that context, and far easier to work around.

Backpatch to all supported branches.

Branch
------
REL9_3_STABLE

Details
-------
http://git.postgresql.org/pg/commitdiff/53b0f213448905c70b629364c318da316005208d

Modified Files
--------------
src/bin/pg_dump/pg_dumpall.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)