Previously UnitTestDataSetBuilderRectilinear and
UnitTestDataSetBuilderRegular did an exhaustive test of all possible
grid sizes within a certain amount of dimensions and with some number of
ways to build point arrays. This created hundreds of thousands of cases
that were checked, and it was running a long time. At best it wasted
time and at worst ctest reported the test as timed out.

It is not really necessary to perform an exhaustive test. The tests are
changed to do 10 trials using random values for dimensions and fill
methods.