update news

Author: philchalmers

NEWS.md

@@ -2,6 +2,8 @@
 
 ## Changes in SimDesign 2.9.1
 
+- `extra_options` gains support for `.options.mpi` to control the MPI properties
+  documented in `doMPI`
 - `quite()` now removes the sunk connection temp file to save storage
   issues (e.g., when distributing on Slurm)
 - `Attach()` gains an `omit` argument to omit specific elements from being attached