A reporting script similar to status_report.py that uses the new
returning supporter method (added in 7aaba96) to provide a list of
how many supporters have started supporting again after lapsing,
bucketed by the number of months for which they had been lapsed.
A new public method, months_expired(), which is similar to the
existing status() in layout, but instead of returning whether the
supporter is new/active/lapsed/etc., it checks to see whether the
supporter is returning after having been lapsed, and if so, returns
the month range corresponding to how long they had been lapsed before
returning as a supporter in the current month.
