Thread: pgsql: Add tab-completion for \unset and valid setting values of psql v

Add tab-completion for \unset and valid setting values of psql variables.

This commit also changes tab-completion for \set so that it displays
all the special variables like COMP_KEYWORD_CASE. Previously it displayed
only variables having the set values. Which was not user-friendly for
those who want to set the unset variables.

This commit also changes tab-completion for :variable so that only the
variables having the set values are displayed. Previously even unset
variables were displayed.

Pavel Stehule, modified by me.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/e15c4ab5fb0de2cab393ed4be2136e1832746412

Modified Files
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doc/src/sgml/ref/psql-ref.sgml |    9 ++-
src/bin/psql/tab-complete.c    |  139 ++++++++++++++++++++++++++++++++++------
2 files changed, 127 insertions(+), 21 deletions(-)