- new hhh4 plot type "maxEV" intended for time-varying neighbourhood weights
- getSeason() and thus plotHHH4_season() and getMaxEV_season() gained an
  argument "unit", which is relevant if the model contains unit-specific
  intercepts or seasonality terms


git-svn-id: svn://svn.r-forge.r-project.org/svnroot/surveillance@831 edb9625f-4e0d-4859-8d74-9fd3b1da38cb