Possibly they are entirely working, but they are hard to debug because doing the numerical derivatives correctly is very tricky, especially shifting the mole fractions while keeping molar density constant. A new method might be needed for testing use only.

closes #33

Replace missing headers as needed

See #16

Fixes the compilation problems, I hope

Python part still needs to be fixed, almost there, compiles in clang again

Add some forceeval and type double where possible