Always output Usage messages to stderr and word-wrap them using `fold -s`

backups/Makefile: Factored backup command into $(backup) for later use by full DB backups. Made Backups, Archived imports sections subsections of Archived imports so Full DB backups can have its own section.

backups/Makefile: Fixed bug where $(SHELL) needed to be set to bash so that $'\n' would be interpreted correctly

backups/Makefile: Fixed bug where *.sql files needed to be restored using psql because pg_restore only supports "non-plain-text formats"

pg_dump_vegbien: For consistency with setting the --schema option, use `set -- "$" args...` to append options to $ which are then passed to pg_dump, instead of specifying several variables which are then included in the pg_dump command

pg_dump_vegbien: Pass command line options directly to pg_dump after parsing out any schema name

backups/Makefile: Don't log stderr or run the command verbosely and instead just output the command and run time to the terminal. This matches what we do for pg_dump, which works better because it just prints the useful information when it's done running.

backups/Makefile: Remove log files after successful restore/extraction because they are only useful for tail -f when the restore operation is running in the background

pg_dump_vegbien: Save owners when saving data (for full export)

pg_dump_vegbien: Use SET SESSION AUTHORIZATION to ensure that owners are always recorded in the same format. This will help make plain text backups comparable using diff.