Changes since 0.1:

o rateplot: The option "grid" was not working, a grid was produced
            anyway. (10/5)

o ncut: Rd file clarified. (11/5)

o stat.table: The "weighted.mean()" function now works correctly for 
              calculating standardized rates.

o Datasets added: thoro, mortDK, gmortDK, blcaIT, lungDK.