Auto-generate Fortran headers #357
Description
The *-kernels/api directories contain Fortran modules that describe the API for each of the C-compatible kernels. These are used in the auto-generation of C++ headers (see #352, #354) and when calling kernels implemented in other languages (e.g. CUDA) from Fortran.
These kernels are currently maintained by hand. It would be better to auto-generate them from the Fortran source.