reorder-tags is a tiny program designed to reorder the tags given in email subjects, to ensure a given order. Tags are expected to be in the form "[<name> #<id>]" with id being numeric. For example, reorder-tags foo bar, will ensure that a Subject containing both [foo #1] and [bar #2], the foo tag will appear befor the bar one. In case the main tag is not present, a new one is prepended with id 0.