show how to compare HNN-core output to data

[jasmainak]

@stephanie-r-jones suggested today that the ERP example should have some comparison with data and perhaps show how the exploration process goes along with computation of RMSE

[ntolley]

If we use something other than the GUI tutorial data, it might be good to show how to resample data where the timestamps may be misaligned using scipy.interpolate.interp1d, since that will probably come up any time you want to compare data.

[jasmainak]

There is an RMSE function in the optimization PR #77 . Maybe worth baking into that ...

[rythorpe]

I think we've moved past this with the new GUI + tutorials. Feel free to reopen if anyone disagrees.