lib/sh/util.sh: command(): support ensuring errors are visible by redirecting them to fd 22 (global stderr) when $stderr_is_errors is set

lib/sh/util.sh: `command`: always prepend -- to the args list (to ensure that the command name is not interpreted as a `command` option), not just when the command alias is used

lib/sh/util.sh: set_global_fds(): increase the log_level so the shadow_fd()/set_fd() function names aren't output at the default verbosity (3), and the redirection commands themselves aren't output at verbosity <= 2. set_global_fds() happens at the beginning of every script that uses util.sh, and is fairly predictable, so it isn't necessary to always echo these commands.

lib/sh/local.sh: psql(): use new convention for command-specific alternate stdout

lib/sh/make.sh: inline_make: use new convention for command-specific alternate stdin

*{.sh,run}: removed extra space between function name and ()

lib/sh/util.sh: streams: moved setting of global stdin/stdout/stderr into set_global_fds () function

lib/sh/util.sh: streams: allow commands to access global stdin/stdout/stderr using fd 20/21/22. this works even when /dev/tty isn't available.

lib/sh/util.sh: streams: added convention that fd 10/11/12 should be used for command-specific alternate stdin/stdout/stderr

lib/sh/util.sh: added streams functions fd_exists, set_fd, shadow_fd, and helpers