pgsql: Clarify pg_upgrade's creation of the map file structure. Also c

Clarify pg_upgrade's creation of the map file structure. Also clean
up pg_dump's calling of pg_upgrade_support functions.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=5cff5b577918cf29e0ba3a35158c27cfe2de280c

Modified Files
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contrib/pg_upgrade/info.c | 72 ++++++++++++---------------------
contrib/pg_upgrade/pg_upgrade.h | 18 ++++++---
contrib/pg_upgrade/version_old_8_3.c | 16 ++++----
src/bin/pg_dump/pg_dump.c | 43 +++++++++++---------
4 files changed, 69 insertions(+), 80 deletions(-)