Handle non-scalar MATLAB structures

[neuromechanist]

Non-scalar structures can be converted to Python objects, for example, the EEG or STUDY structures from EEGLAB can be victims:

", "CURRENTSET": "2.0", "CURRENTSTUDY": "0.0", "EEG": "", "LASTCOM": [], "PLUGINLIST": "", "STUDY": [], "freqs": "[[0.0],[1.0],[2.0],[3.0],...,[64.0]]", "globalvars": "['ALLCOM', 'ALLEEG', 'CURRENTSET', 'CURRENTSTUDY', 'EEG', 'LASTCOM', 'PLUGINLIST', 'STUDY']", "spectra": "[[16.742037097885316,19.688018745267804,15.71891718942258,12.237790562719223,9.422334658565108,...,-19.301965208108534]]", "tmpEEG": "{'name': 'EEG', 'size': matlab.double([[1.0,1.0]]), 'bytes': 4358774.0, 'class': 'struct', 'global': True, 'sparse': False, 'complex': False, 'nesting': {'function': '', 'level': 1.0}, 'persistent': False}"}, "figures": []}">

{"output": "", "error": null, "workspace": {"ALLCOM": [], "ALLEEG": "", "CURRENTSET": "2.0", "CURRENTSTUDY": "0.0", "EEG": "", "LASTCOM": [], "PLUGINLIST": "", "STUDY": [], "freqs": "[[0.0],[1.0],[2.0],[3.0],...,[64.0]]", "globalvars": "['ALLCOM', 'ALLEEG', 'CURRENTSET', 'CURRENTSTUDY', 'EEG', 'LASTCOM', 'PLUGINLIST', 'STUDY']", "spectra": "[[16.742037097885316,19.688018745267804,15.71891718942258,12.237790562719223,9.422334658565108,...,-19.301965208108534]]", "tmpEEG": "{'name': 'EEG', 'size': matlab.double([[1.0,1.0]]), 'bytes': 4358774.0, 'class': 'struct', 'global': True, 'sparse': False, 'complex': False, 'nesting': {'function': '', 'level': 1.0}, 'persistent': False}"}, "figures": []}