pgsql: Allow embedded spaces without quoting in unix_socket_directories

Allow embedded spaces without quoting in unix_socket_directories entries.

This fix removes an unnecessary incompatibility with the old behavior of
the unix_socket_directory parameter. Since pathnames with embedded spaces
are fairly popular on some platforms, the incompatibility could be
significant in practice. We'll still strip unquoted leading/trailing
spaces, however.

No docs update since the documentation already implied that it worked
like this.

Per bug #7514 from Murray Cumming.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/d2286a98ef3fb88bafb57381b4c20b8b878827f1

Modified Files
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src/backend/utils/adt/varlena.c | 21 ++++++++++++---------
1 files changed, 12 insertions(+), 9 deletions(-)