Include module dependencies in Makefile

[danielhollas]

Currently, Fortran module dependencies are not correctly resolved in the src/Makefile.
Because of this, parallel compilation is not supported and will fail ungracefully, as reported in #148.
This also means that if module dependencies are changed, the recompilation may fail (one needs to run make clean before recompiling).

To properly solve this, we need to generate the dependencies dynamically via a some script and include them in the Makefile.