Add C and Fortran wrappers for MPI_Init_thread

[wangvsa]

Description

Add C and Fortran wrappers for MPI_Init_thread. Some applications, such as GAMESS and FLASH, use multi-threaded MPI.

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Performance enhancement (non-breaking change which improves efficiency)
• [ ] Code cleanup (non-breaking change which makes code smaller or more readable)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)
• [ ] Testing (addition of new tests or update to current tests)
• [ ] Documentation (a change to man pages or other documentation)