Spike sorting updates and snapshot class
- Snapshot class to register images as notes in Alyx
- Ephys pipeline: RawEphysQC: outputs channels labels as part of pipeline
- Ephys pipeline: spike sorting
- dsp.voltage: destripe detects bad channels and interpolate them
- synchronisation 3B: gives a 10% leeway to throw exception
- spikes sorting task outputs the RMS plot