pg_ctl changes

I've implemented the following changes in pg_ctl:

* Make -w the default for shut down, add -W option to specify no wait.

* Add -l option to name log file. If the option is omitted, then the
postmaster log goes to stdout, so you can use 'pg_ctl ... > log' and still
get pg_ctl's stderr on the terminal.

* Proper file descriptor redirection to allow postmaster to detach from
shell's process group.

* Add -s option to turn off informational messages, so as to not mess up
the carefully crafted Red Hat-style startup screens. Error messages still
show up.

This should make pg_ctl a lot more suitable for startup scripts and
overall. If this is okay then I'll also try to merge the contrib/linux
and contrib/init.d scripts and reflect these changes there.

--
Peter Eisentraut peter_e(at)gmx(dot)net http://yi.org/peter-e/