[KLeoUIC]

Pull Request Description

Currently documentation is very minimal or boilerplate and aimed at developers and those familiar with MPI. It leaves a gap for those learning MPI through MPICH and users looking to orient themselves in the large standard. As MPIX functions are not in the standard yet users have no easy way of looking up their usage beyond the one sentence description manpages have currently. The generated descriptions provide a way of getting more information for users who do not wish to scour the codebase or search for papers where the function was proposed.

Pull request provides semantic descriptions based off of the latest MPI Standard and source code.
Directions and script for making new descriptions in Box.

Author Checklist

• Provide Description
  Particularly focus on why, not what. Reference background, issues, test failures, xfail entries, etc.
• Commits Follow Good Practice
  Commits are self-contained and do not do two things at once.
  Commit message is of the form: module: short description
  Commit message explains what's in the commit.
• Passes All Tests
  Whitespace checker. Warnings test. Additional tests via comments.
• Contribution Agreement
  For non-Argonne authors, check contribution agreement.
  If necessary, request an explicit comment from your companies PR approval manager.

[hzhou]

test:mpich/doc

[hzhou]

test:mpich/doc

[sonjahapp]

I reviewed text for MPI Session and spawn procedures. Text looks good to me except for the single comment I made on MPI_Comm_spawn.