Interval Algebra: Composition Formulas First Draft

composition_formulas.py now can learn formulas using [ffx](https://github.com/natekupp/ffx), but [will probably take for ever](https://github.com/natekupp/ffx/issues/14).

Also [having a look at shogun](https://github.com/shogun-toolbox/shogun/issues/1784) as an alternative...