added get_h5files

Bug in sampling was selecting empty traps.

image_id found from OMERO; added skip_channels

Error was in asking for non-existing cells.

Using Arin's code.
Renamed directories to include Arin's name.

Renamed butterworth_filter to flavin_filter.

Includes butterworth, periodogram, snr.

Better to interpolate NaNs than to drop them, which changes
spacing between time points.

Mimics aliby's.

To ease imports.

Reorganised to follow poetry's standard directory structure.

Includes pathos and napari.