Generate some automatic testing

[Andrew-Clappison]

Make unit tests based off of the current WhoBPyT examples that doesn't require visual inspection

[Andrew-Clappison]

@sbastiaens has examples to use as a reference

[P-Oveisi]

@Andrew-Clappison would the testing be more qualitative (i.e., does the code run properly?) or quantitative (i.e., how well it fits data, etc.)?

[P-Oveisi]

At this point, I'm implementing simple verification of parameter fitting in terms of making sure that the ones we indicated as free parameters are changing while the rest are not.

The fitting status for the parameters can be found in the Model_fitting object, where the intent to fit or not is within Model_fitting.model.params and the actual fitted params are found in Model_fitting.trainingStats.fit_params

code here
example notebook here
(there's an error due to pandas version that I haven't figured out yet)

Not sure if this is the direction we're looking at, don't want to commit to it too hard before getting some input from others.

[Davi1990]

@P-Oveisi please split the PR

[Davi1990]

@tmorshed is working on automating it on PR #138.
Waiting for the tests to be generated by @kevinkadak and @P-Oveisi