v0.3.1

What's Changed

Code improvements:

• Fix MPI to be symmetric in #47
• Cleaner rust import in #54

Documentation:

• 35 update docs by @frank1010111 in #36
• 📝 add MPI example by @frank1010111 in #47
• Submit to joss by @frank1010111 in #50

Full Changelog: v0.3.0...v0.3.1