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 :-/

<?xml version="1.0" encoding="UTF-8" ?>
<datacage>
    <user>SA</user>
    <password/>
    <driver>org.h2.Driver</driver>
    <url>jdbc:h2:${artifacts.config.dir}/../h2/datacage</url>
</datacage>