Create Fortran wrapper library for MUSICA

[mattldawson]

1. Remove the ccpp directory from CMakeLists.txt
2. Create src/fortran_interface and add it to the cmake build
   • make sure to include the directory in src/CMakeLists.txt
   • create src/fortran_interface/CMakeLists.txt
3. Define a new cmake target similar to what is done here
   • call it fortran_interface, aliased with musica::fortran_interface
4. For the new target, you'll need to setup several properties like here.
   • crucially, this sets up the Fortran_MODULE_DIRECTORY so that the .mod files get copied to a place where other targets can find it
   • make a new cmake variable to allow someone to chose the module directory
5. Copy the fortran interface to the C functions to micm from here and put them in src/fortran_interface/some file

Acceptance criteria

a project can include musica::musica-fortran and use the c interface

Write a dockerfile that builds and install musica. Then, create a new cmake project that sets up a tiny fortran example that expects to use the musica::musica_fortran target. We should see the example files and the musica::musica_fortran target be compiled and a link against -lmusica in the compile output.

[boulderdaze]

Merged into main