pgsql: Add "\pset linestyle ascii/unicode" option to psql, allowing our

Log Message:
-----------
Add "\pset linestyle ascii/unicode" option to psql, allowing our traditional
ASCII-art style of table output to be upgraded to use Unicode box drawing
characters if desired. By default, psql will use the Unicode characters
whenever client_encoding is UTF8.

The patch forces linestyle=ascii in pg_regress usage, ensuring we don't
break the regression tests in Unicode locales.

Roger Leigh

Modified Files:
--------------
pgsql/doc/src/sgml/ref:
psql-ref.sgml (r1.231 -> r1.232)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/psql-ref.sgml?r1=1.231&r2=1.232)
pgsql/src/bin/psql:
command.c (r1.209 -> r1.210)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/command.c?r1=1.209&r2=1.210)
mbprint.c (r1.35 -> r1.36)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/mbprint.c?r1=1.35&r2=1.36)
mbprint.h (r1.13 -> r1.14)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/mbprint.h?r1=1.13&r2=1.14)
print.c (r1.116 -> r1.117)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/print.c?r1=1.116&r2=1.117)
print.h (r1.40 -> r1.41)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/print.h?r1=1.40&r2=1.41)
tab-complete.c (r1.186 -> r1.187)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/psql/tab-complete.c?r1=1.186&r2=1.187)
pgsql/src/test/regress:
pg_regress_main.c (r1.6 -> r1.7)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/pg_regress_main.c?r1=1.6&r2=1.7)