message: DOC: document known issues with MPI3 shared memroy
  Add known issues encounted when using MPI3 shared memory to
  the "Known Bugs" section of the Release Notes.
  This refers to issue
diff: @@ -120,12 +120,16 @@ The Axom project release numbers follow [Semantic Versioning](http://semver.org/
  - Third-party libraries can now build on the Windows platform through uberenv using vcpkg
  ("zero-to-axom support on Windows")
  -### Known Bugs
  +### Known Issues
  - Encountered a compiler bug on IBM LC platforms when using the IBM XL C/C++
  compiler. The issue is manifested in the `generate_aabbs_and_centroids` method
  in the `spin_bvh.cpp` unit test. It seems that the compiler does not handle
  the lambda capture of the arrays correctly which leads to a segfault. A
  workaround for the IBM XL compiler is provided.
  +- There is known bug in MVAPICH that prevents consecutive creation/deletion
  + of MPI windows. This was encountered on LC platforms when enabling shared
  + memory in the Signed Distance Query. See the corresponding
  + [Github Issue](https://github.com/LLNL/axom/issues/257) for details.
  ## [Version 0.3.3] - Release date 2020-01-31
  