29 together, resulting in 365 bins per year that align
% with calendar dates, even in leap years.  'month' bins data by calendar
% month, resulting in 12 bins per year.
%
% |[xg, yr] = reshapetimeseries(t, x, 'func', @func)| applies the function
% handle |@func| to data in a bin.  @func should accept a vector of values
% and return a scalar.  The default is to average data (i.e. @nanmean).
%
% |[xg, yr] = reshapetimeseries(t, x, 'yrlim', yrlim)| returns a reshaped
% grid of data spanning the year limits in 