pgsql: Don't run regression tests in SQL_ASCII encoding by default

Don't run regression tests in SQL_ASCII encoding by default

Instead, run them in the encoding that the locale selects, which is
more representative of real use.

Also document how locale and encoding for regression test runs can be
selected.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=35eb0958be476d58dcc8ba462d57384e74a62d88

Modified Files
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doc/src/sgml/regress.sgml    |   42 ++++++++++++++++++++++++++++++++++++++++++
src/test/regress/GNUmakefile |    5 +----
2 files changed, 43 insertions(+), 4 deletions(-)