Not possible to export anything else than Document objects
Currently the exporter component does not allow to list anything else than document objects.
Looks like the table query does not properly handle the object types declared.
As an example the Fedora repository could export assessments as well as documents if he could.
Install: Add extra setting of sql_mode to "" to avoid NO_ZERO_DATE in 1.9 to 1.10 upgrade - see #2574