fix: lib/sh/db.sh: psql(): removed debugging changes

bugfix: lib/sh/util.sh: highlight_log_msg(): when not can_highlight_log_msg, need to remove any surrounding formatting

fix: lib/sh/util.sh: die_error_hidden(): always log local vars at same log_level as echo_func

fix: *{.sh,run}: always log kw_params at same log_level as echo_func

lib/sh/util.sh: split_lines(): usage: matched up and synced different syntaxes

bugfix: lib/sh/util.sh: log_msg!(): split_lines does not support being invoked by wrapper; need to use `declare lines; wrapper "split_lines" str` instead

fix: lib/sh/util.sh: split_lines(): usage: documented different syntax for when using wrapper

bugfix: lib/sh/util.sh: die_error_hidden(): echo_func to assist debugging

bugfix: lib/sh/util.sh: split(): need to limit the effects of IFS to just the splitting, so it doesn't cause strange errors in other functions

bugfix: stderr2stdout(): fd 2 must be redirected back to fd 2, not log-filtered, in case there are other errors in addition to the benign error. this fixes a bug in pg_schema_exists(), where errors about the DB being down were not displayed because they were log-filtered out.