pgsql: Accept pg_ctl timeout from the PGCTLTIMEOUT environment variable

Accept pg_ctl timeout from the PGCTLTIMEOUT environment variable.

Many automated test suites call pg_ctl. Buildfarm members axolotl,
hornet, mandrill, shearwater, sungazer and tern have failed when server
shutdown took longer than the pg_ctl default 60s timeout. This addition
permits slow hosts to easily raise the timeout without us editing a
--timeout argument into every test suite pg_ctl call. Back-patch to 9.1
(all supported versions) for the sake of automated testing.

Reviewed by Tom Lane.

Branch
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REL9_5_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/725f0ce29690b7e98d18290c9ab69b7a2bab3715

Modified Files
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doc/src/sgml/ref/pg_ctl-ref.sgml | 15 ++++++++++++++-
src/bin/pg_ctl/pg_ctl.c | 10 +++++++++-
2 files changed, 23 insertions(+), 2 deletions(-)