Support stimulus_template as optional column in IntracellularRecordingsTable

[stephprince]

Motivation

Fix #1747 to support stimulus_template as a predefined optional column of the IntracellularStimuliTable
(See NeurodataWithoutBorders/nwb-schema#545 for the related schema PR)

Since the proposed column neurodata type is TimeSeriesReferenceVectorData, I though it was maybe unclear how to add data to the column so I added an example in the tutorials.

The IntracellularRecordingsTable.add_recording had some nice functionality to automatically compute the start_index and count values for stimulus time series inputs, as well as handle recordings with no stimulus info provided. I added similar behavior for stimulus_template, but I'm not sure if that's something that would be helpful or if it's best to add additional stimulus template data via the stimulus_metadata argument

How to test the behavior?

from pynwb.base import TimeSeriesReferenceVectorData
from pynwb.testing.mock.file import mock_NWBFile
from pynwb.testing.mock.icephys import (mock_IntracellularRecordingsTable,
                                        mock_VoltageClampStimulusSeries,
                                        mock_IntracellularElectrode,)

# adding data by row
nwbfile = mock_NWBFile()
electrode = mock_IntracellularElectrode(nwbfile=nwbfile)
stimulus = mock_VoltageClampStimulusSeries(nwbfile=nwbfile)
nwbfile.add_intracellular_recording(electrode=electrode,
                                    stimulus=stimulus,
                                    stimulus_template=stimulus)

# adding data by column
irt = mock_IntracellularRecordingsTable()
irt.add_column(name='stimulus_template',
               description='',
               category='stimuli',
               col_cls=TimeSeriesReferenceVectorData,
               data=[(0, 5, stimulus),
                     (0, 5, stimulus),
                     (0, 5, stimulus),
                     (0, 5, stimulus),
                     (0, 5, stimulus),])

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (d0c4068) 91.99% compared to head (a7d1f56) 92.02%.

Additional details and impacted files

@@                 Coverage Diff                  @@
##           nwb-schema-2.7.0    #1815      +/-   ##
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+ Coverage             91.99%   92.02%   +0.03%     
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  Files                    27       27              
  Lines                  2623     2633      +10     
  Branches                685      690       +5     
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+ Hits                   2413     2423      +10     
  Misses                  138      138              
  Partials                 72       72              

Flag	Coverage Δ
integration	70.94% <30.00%> (-0.16%)	⬇️
unit	83.74% <100.00%> (+0.06%)	⬆️

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[oruebel]

Looks overall good to me. I added a couple of comments for the tutorial part but those should be easy to fix.

[oruebel]

Looks good to me. @rly is doing a final review an will approve once ready.

[rly]

@oruebel because you requested changes earlier, you still need to approve this