API documentation

[andreaslundell]

Document the API, e.g. how to create and solve a model from an external program:

• [x] create an example in the model tests.
• [ ] document this on the project web site.
• [x] example on how to use the termination callback.

[andreaslundell]

This is under work in https://github.com/coin-or/SHOT/tree/apiexample.