pgsql: Update ALTER TABLE docs to mention using VACUUM FULL for rewrite

Update ALTER TABLE docs to mention using VACUUM FULL for rewrites.

Remove the claim that ALTER TABLE .. SET DATA TYPE is the fastest way of
rewriting a table, since it no longer is.

Noah Misch and Robert Haas, based on a suggestion from Tom Lane.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=edad08ba545b43261b4d54d65122b45c9b5ee801

Modified Files
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doc/src/sgml/ref/alter_table.sgml |   23 ++++++++---------------
1 files changed, 8 insertions(+), 15 deletions(-)