Signficant refactor of the adjoint domain/tally for the expected
value estimator. My previous implementation tallied with the tranpose
of the iteration matrix. Okten in his paper switches nomenclatures,
using the more confusion one where he calls the adjoint method the
direct method. Because of this I needed to implement the expected
value estimator with the non-transposed iteration matrix. The
original collision estimator functionality is intact but the
expected value estimator needs some work.