Prepare adapter for full integration

[BenjaminRodenberg]

Goal: inline in the actual ccx code using #ifdefs

Note: I copied this issue from our internal list of todos to make it more visible. Please feel free to directly edit the header, if you can provide more details on the rationale behind this approach. I guess that one reason is that maintaining the Makefile of this adapter is painful, but I'm overview of the CalculiX adapter.