Post-CMake merge and 3.0 items

[ndellingwood]

Reminder list of items following merge of #471 (previous) now #491

• [x] Re-enable -Werror for the clang builds on kokkos-dev-2 when we resume testing off of Kokkos' develop branch
• [x] Add more testing configurations to kokkos-dev-2 (cover items in spot-check)
• [x] Convert testing to use test_all_sandia replacement script patterned from kokkos' cm_test_all_sandia script

[ndellingwood]

Some open issues to resolve for 3.0 testing and release:

• [x] spgemm shmem alignment issues: Issue #500 PR #503 @ndellingwood

• [x] spmv unit testing tolerance settings: Issue #506 PR #507 ? @lucbv

• [x] dot-based GEMM (Cuda spec) handling of beta==0 case: Issue #509 @seheracer Follow-up - possible slight loosening of tolerance in failing Trilinos tests to allow for diffs caused by the parallelism introduced by these performance enhancements

• [x] spgemm symbolic phase fixes (mem pool, ...) @brian-kelley See trilinos/Trilinos#6237

• [x] update of Ifpack2 calls to *gauss_seidel_apply in packages/ifpack2/src/Ifpack2_Relaxation_def.hpp - needs to be added to the kokkos-promotion branch

• [x] resolve issues during Trilinos configuration with call to KOKKOS_CHECK at line 113 of kokkos-kernels/CMakeLists.txt (function is defined in kokkos file kokkos/cmake/KokkosConfig.cmake.in) @jjwilke

Adding @srajama1 @crtrott and @jjwilke so they are in the loop.

Edit: Added link to kokkos-promotion branch of Trilinos.

[ndellingwood]

Issues to resolve exposed by Trilinos testing:

• [x] batched_lu_serial: fix for ambiguous ? operation error (Sacado) : PR #512

[ndellingwood]

• [x] Recent issue in ATDM testing with Tpetra MV following #510 -related patch
  See trilinos/Trilinos#6418

[ndellingwood]

• [x] gemv transpose mode with TPLs #539
• [x] perf test link errors #527

[ndellingwood]

This was all completed for 3.0, closing.