Tpetra::CrsMatrix: Deprecate and remove localSolve
Created by: mhoemmen
@trilinos/tpetra @trilinos/ifpack2
As discussed in #514 (closed), sparse triangular solve properly belongs to a solver or preconditioner package, rather than to Tpetra. Removing this method would reduce the amount of code to build in Tpetra. It would also give us the freedom to reduce the cost of fillComplete, by not computing local constants (like whether the matrix is upper or lower triangular).
Tpetra::CrsMatrix::localSolve does give Tpetra users a way to solve triangular systems where the vectors have a different Scalar type than the matrix. However, KokkosSparse::trsv already exposes this functionality. Furthermore, putting a local sparse triangular solve in Tpetra may confuse users who think of Tpetra as offering global computational kernels, and who don't understand the difference between "local" and "global."