fluxSummary regression

• seems to be related to c3571b73

Searching for cellZoneDirection returns zero regions. This cascades further, since the lists are now zero-sized and makes all further accesses segfault.

For testing - added tutorial test angledDuct/implicit

fluxSummary
{
    type    fluxSummary;
    libs    (fieldFunctionObjects);

    scaleFactor     1.205;
    write           yes;
    log             yes;
    mode            cellZoneAndDirection;
    cellZoneAndDirection
    (
        (porosity (1 1 0))
    );
}

@Prashant @Mattijs