Added a new control 'show legend' to the map's toolbar. This control opens a window that displays the legends of all activated layers. Currently, the row in that window has a fixed size of 400x150. The size is fixed, because there are problems with SmartGWT to build panels with auto height/width :-/

select.abflusstafel = SELECT ABFLUSSTAFEL_NR, \
                             ABFLUSSTAFEL_BEZ, \
                             GUELTIG_VON, \
                             GUELTIG_BIS, \
                             PEGELNULLPUNKT FROM ABFLUSSTAFEL WHERE MESSSTELLE_NR LIKE :number