Add Makefile for zipping reciepts to send to my accountant.

last_month != date +%Y-%m --date 'last month'

last_zip != ls *.zip | sort -r | head -1

new_files != find reciepts/ -type f -newer ${last_zip}

${last_month}.zip: ${new_files}

	zip $@ $^

.PHONY: clean

clean:

	rm *.zip