wip/py-gotran 2020.2.0 NetBSD

TODO: Adjust the following lines from README.md

# Gotran - General ODE TRAnslator

Gotran:

• provides a Python interface to declare arbitrary ODEs.

• provides an interface for generating CUDA/C/C++/OpenCL/Julia/Python/Matlab code for a number of functions including the right hand side and symbolic generation of a Jacobian.

• is intentionally lightweight, and could be interfaced by other Python libraries needing functionalities to abstract a general ODE.

• depends on NumPy, and on SymPy. See further instructions in INSTALL

• can load models from external ODE description files such as CellML

## Documentation ...