pgsql: Add an example of attaching a default value to an updatable view

Add an example of attaching a default value to an updatable view.

This is probably the single most useful thing that ALTER VIEW can do,
particularly now that we have auto-updatable views.  So show an explicit
example.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/3a1f8cdfa90443117049c601364009b71eaad3d1

Modified Files
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doc/src/sgml/ref/alter_view.sgml |   14 +++++++++++++-
1 files changed, 13 insertions(+), 1 deletions(-)