lib/sh/util.sh: sed: use case statement instead of test to determine flag letter, to easily allow matching multiple `uname` OSes or adding additional flag letters

lib/sh/util.sh: die(): documented that its msg can use $?, because it has not yet been overridden by another command

lib/sh/util.sh: die_e(): use die(), which performs the necessary save_e/rethrow. this requires using $? instead of $e for the exit status, because $e has not yet been set.

lib/sh/util.sh: inlined log_e() into die_e() because that's the only place it's used

lib/sh/util.sh: command(): print "command exited with error" message using new die_e() if command returns false. this requires removing manual die_e()/log_e() calls elsewhere.

lib/sh/util.sh: command(): moved increase of indent inside () so that error-handling statements after () will use the outer log_level

lib/sh/util.sh: added die_e(), which logs that a command exited with an error

lib/sh/util.sh: command(): determine redirections before echoing the command so they can be logged along with the command, instead of as separate exec statements. (these had a higher log_level to avoid cluttering the output with `exec` lines, which usually suppressed the redirections completely.) inline the command__set_fds() nested func so the redirections are all in one place.

lib/sh/util.sh: use simpler `if can_log; then indent; fi` instead of `can_log && indent || true`. however, the `&& indent || true` syntax is still required in aliases such as echo_func which need to allow prefixing the command with a wrapper command or kw param assignments.

inputs/GBIF/raw_occurrence_record/run: dynamically generate herbaria_filter.csv_ from herbaria.ih in new target herbaria_filter.csv_/make()