Pacify flake8

[oesteban]

The linter currently complains about a lot of problems:

$ flake8 nirodents/
nirodents/workflows/brainextraction.py:7:1: F401 'collections.OrderedDict' imported but unused
nirodents/workflows/brainextraction.py:8:1: F401 'multiprocessing.cpu_count' imported but unused
nirodents/workflows/brainextraction.py:14:1: F401 'nipype.Function' imported but unused
nirodents/workflows/brainextraction.py:22:1: F401 'niworkflows.utils.misc.get_template_specs' imported but unused
nirodents/workflows/brainextraction.py:23:1: F401 'niworkflows.interfaces.ants.ThresholdImage' imported but unused
nirodents/workflows/brainextraction.py:33:1: F401 'niworkflows.interfaces.utils.CopyXForm' imported but unused
nirodents/workflows/brainextraction.py:34:1: F401 'niworkflows.interfaces.nibabel.Binarize' imported but unused
nirodents/workflows/brainextraction.py:68:23: F821 undefined name 'get_template'
nirodents/workflows/brainextraction.py:68:60: F821 undefined name 'debug'
nirodents/workflows/brainextraction.py:68:78: F821 undefined name 'tpl_suffix'
nirodents/workflows/brainextraction.py:69:24: F821 undefined name 'get_template'
nirodents/workflows/brainextraction.py:69:61: F821 undefined name 'debug'
nirodents/workflows/brainextraction.py:72:41: F821 undefined name 'tpl_path'
nirodents/workflows/brainextraction.py:73:32: F821 undefined name 'tpl_path'
nirodents/workflows/brainextraction.py:75:40: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:75:42: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:83:25: E127 continuation line over-indented for visual indent
nirodents/workflows/brainextraction.py:117:47: E261 at least two spaces before inline comment
nirodents/workflows/brainextraction.py:117:48: E262 inline comment should start with '# '
nirodents/workflows/brainextraction.py:165:53: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:165:55: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:165:58: E231 missing whitespace after ','
nirodents/workflows/brainextraction.py:170:56: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:170:58: E201 whitespace after '['
nirodents/workflows/brainextraction.py:170:70: E202 whitespace before ']'
nirodents/workflows/brainextraction.py:174:47: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:174:49: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:176:47: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:176:49: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:176:72: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:176:74: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:187:54: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:187:56: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:187:59: E231 missing whitespace after ','
nirodents/workflows/brainextraction.py:191:55: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:191:57: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:191:59: E201 whitespace after '['
nirodents/workflows/brainextraction.py:191:71: E202 whitespace before ']'
nirodents/workflows/brainextraction.py:192:20: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:192:22: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:194:22: E225 missing whitespace around operator
nirodents/workflows/brainextraction.py:195:55: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:195:57: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:195:59: E201 whitespace after '['
nirodents/workflows/brainextraction.py:195:71: E202 whitespace before ']'
nirodents/workflows/brainextraction.py:196:20: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:196:22: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:200:24: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:200:26: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:200:54: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:200:56: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:201:21: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:201:23: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:201:49: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:201:51: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:202:29: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:202:31: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:202:49: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:202:51: E251 unexpected spaces around keyword / parameter equals
nirodents/workflows/brainextraction.py:210:9: E265 block comment should start with '# '
nirodents/workflows/brainextraction.py:246:9: E265 block comment should start with '# '
nirodents/workflows/brainextraction.py:256:9: E265 block comment should start with '# '
nirodents/workflows/brainextraction.py:261:9: E265 block comment should start with '# '

We should address all these.

[oesteban]

Done with #27