Legend items order when using diff_waveform in plot_conditions

[sotofernando]

ℹ Computer information

• Platform OS: Mac
• Python Version: 3.7
• Brain Interface Used: Muse

📝 Provide detailed reproduction steps (if any)

1. Run examples/visual_p300/01r__p300_viz.py

✔️ Expected result

I think is just changing order when concatenating lists in https://github.com/NeuroTechX/eeg-notebooks/blob/master/eegnb/analysis/utils.py#L307

Instead of:

        legend = ["{} - {}".format(diff_waveform[1], diff_waveform[0])] + list(
            conditions.keys()
        )

could be something like: legend = list(conditions.keys()) + ["{} - {}".format(diff_waveform[1], diff_waveform[0])]

❌ Actual result

📷 Screenshots

To check and identify wave forms and legend items, I compared with Alexandre's article in: http://alexandre.barachant.org/blog/2017/02/05/P300-with-muse.html