pgsql: In pg_upgrade, check that the binary and data directories are th

In pg_upgrade, check that the binary and data directories are the same
major version.

Backpatch to 9.1.

Dan McGee

Branch
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REL9_1_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/d9db32401c1477fb63fb47a376fc0d08605dcc9b

Modified Files
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contrib/pg_upgrade/check.c | 50 ++++++++++++++++++++++++++++++++++++++-
contrib/pg_upgrade/pg_upgrade.h | 1 +
2 files changed, 50 insertions(+), 1 deletions(-)