Trilinos: Ifpack2: UnitTestSingleProcessRILUK's tests for (alpha, beta) cases tests only default case.

[ambrad]

@trilinos/ifpack2: The unit test calls

crsmatrix->apply (x_copy, y_copy, Teuchos::NO_TRANS, alpha, beta);

for the various cases, but not

prec.apply(y, x, mode, alpha, beta);

I believe the second is what was intended. Fix this to get coverage of these non-default cases. This was discovered in the course of PR #1594.

[ambrad]

New test would have caught the RILUK::apply() bug. Will soon run checkin script.