pgsql: Code and docs review for multiple -c and -f options in psql.

Code and docs review for multiple -c and -f options in psql.

Commit d5563d7df94488bf drew complaints from Coverity, which quite
correctly complained that one copy of each -c or -f string was being
leaked. What's more, simple_action_list_append was allocating enough space
for still a third copy of each string as part of the SimpleActionListCell,
even though that coding method had been superseded by a separate strdup
operation. There were some other minor coding infelicities too. The
documentation needed more work as well, eg it forgot to explain that -c
causes psql not to accept any interactive input.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/fcbbf82d2b6caf7b156f2ec35b322e23caf1e99e

Modified Files
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doc/src/sgml/ref/psql-ref.sgml | 140 +++++++++++++++++++++++-----------------
src/bin/psql/startup.c | 93 ++++++++++++--------------
2 files changed, 121 insertions(+), 112 deletions(-)