Consider providing required tolerance to the linear solver

[pelesh]

Some linear solvers used in HiOp (MA57, STRUMPACK) use iterative refinement to get sufficient accuracy to the solution of the underlying linear system. It might be a good idea for HiOp to provide required tolerance to the linear solvers through the linear solver interface. That may help avoid unnecessary refinement iterations and improve the overall performance of HiOp.

CC @cnpetra