SCHEMA: Issues to implement

The following BIDS Validator issues should be implementable without further changes to the schema:

[x] TOO_FEW_AUTHORS (length(json.Authors) > 1, select dataset_description.json)
[x] SLICETIMING_VALUES_GREATOR_THAN_REPETITION_TIME
[x] EFFECTIVEECHOSPACING_TOO_LARGE
[x] ECHOTIME1_2_DIFFERENCE_UNREASONABLE (phasediff only; implementing for phase1/phase2 would be a bonus)
[x] SLICETIMING_ELEMENTS
[x] REPETITIONTIME_PREPARATION_NOT_CONSISTENT
[x] VOLUME_TIMING_AND_REPETITION_TIME_MUTUALLY_EXCLUSIVE (needs issue annotation, possibly reimplement in checks)
[x] NIFTI_DIMENSION
[x] NIFTI_UNIT
[x] NIFTI_PIXDIM
[x] BOLD_NOT_4D
[x] SFORM_AND_QFORM_IN_IMAGE_HEADER_ARE_ZERO
[x] ~~NIFTI_PIXDIM4~~ Implementation detail of old Nifti parser; covered by BOLD_NOT_4D and REPETITION_TIME_MISMATCH
[x] MAGNITUDE_FILE_WITH_TOO_MANY_DIMENSIONS
[x] T1W_FILE_WITH_TOO_MANY_DIMENSIONS
[x] REPETITION_TIME_GREATER_THAN
[x] ECHO_TIME_GREATER_THAN
[x] ECHO_TIME_DIFFERENCE_GREATER_THAN
[x] TOTAL_READOUT_TIME_GREATER_THAN
[x] REPETITION_TIME_MISMATCH
[x] EFFECTIVEECHOSPACING_LARGER_THAN_TOTALREADOUTTIME
[x] POST_LABELING_DELAY_GREATER
[x] BOLUS_CUT_OFF_DELAY_TIME_GREATER
[x] LABELING_DURATION_GREATER
[x] ECHO_TIME_ELEMENTS
[x] "Participants age 89 or higher" (yes, this really is the code; change it to something consistent)
[x] MISSING_TSV_COLUMN_IEEG_CHANNELS - Update rules.tabular_data.ieeg.iEEGChannels.initial_columns
[x] MISSING_TSV_COLUMN_IEEG_ELECTRODES - Update rules.tabular_data.ieeg.iEEGElectroes.initial_columns
[x] STIMULUS_FILE_MISSING - checks: [exists(columns.stim_file, "stimuli") == length(columns.stim_file)]

The following issues can be implemented at present by using the selector path == '/dataset_description.json' to ensure that they're only run once (a different approach may be justified later):

[x] SAMPLES_TSV_MISSING
[x] SUBJECT_FOLDERS
[x] PARTICIPANT_ID_MISMATCH
[x] PHENOTYPE_SUBJECTS_MISSING

bids-standard / bids-specification

SCHEMA: Issues to implement #1402