Softwaretests...20181219 10.1/10.2/10.5/10.9: corrected computation of missing volume and excavation volume, date range for density queries as in Sinfo/Tkh, empty values instead of 0 if computation not possible

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