Case evaluation model for div and mod.

[apercov]

The case evaluation model was updated with the ticket 2190. However, queries containing div and mod operators are getting evaluated with old model, which is drastically slower.
Also old model fails when it contains arrays that do not adhere to the same tiling scheme.

E.g. these queries in the systemtest:

----------------------------------------------------------------------
induction_all_operations_int_divide.rasql
select (case when test_grey2 = 0 then 0c else div(test_grey, test_grey2)
end) from test_grey, test_grey2
----------------------------------------------------------------------
induction_all_operations_modulo.rasql
select (case when test_grey2 = 0 then 0c else mod(test_grey, test_grey2)
end) from test_grey, test_grey2

.. fail when test_grey and test_grey2 (mr collections basically) are
inserted with different tiling schemes:

rasql --user rasadmin --passwd rasadmin -q 'create collection test_grey
GreySet'
rasql --user rasadmin --passwd rasadmin -q 'create collection test_grey2
GreySet'
rasql --user rasadmin --passwd rasadmin -q 'insert into test_grey values
decode($1 ) tiling aligned [0:49,0:29] tile size 1500' -f
$RMANSRC/src/systemtest/testcases_mandatory/test_select/testdata/mr_1.png

rasql --user rasadmin --passwd rasadmin -q 'insert into test_grey2 values
decode($1 ) tiling aligned [0:29,0:59] tile size 1800' -f
$RMANSRC/src/systemtest/testcases_mandatory/test_select/testdata/mr_1.png