Use python convolutions also for positivity predictions
Created by: scarlehoff
For this I had to introduce a new attribute and an if
condition in the predictions module. Another option is to create a fake op and fake cuts in the positivity spec class I guess.
The first commit includes only the if
condition and the extra attribute to create a record of the cpp and the python version giving the same result, I'll push the change to PositivityResult later if that passes.