Compiler and its flags should be separated
Rename `UTILS_HAVE_ALREADY_LOADED` -> `_FORTRAN_LIB_H_`
Rename `USE_UTILS_H` -> `USE_FORTRAN_LIB_H`
Rename `utils.h` -> `fortran_lib.h`
BUG: typos
Iteration should finish if `g` is orthogonal to `A`
Merge branch 'utils_h-to-fortran_lib_h'
Add `Makefile` at the top-level (src/Makefile should be replaced by this file in the future)
Merge branch 'toplevel-Makefile'