Update Flake8 config

Fixes Python linting errors.

setup.cfg

@@ -21,29 +21,55 @@ exclude =
     sphinx-doc/source/conf.py,
     django/applications/catmaid/migrations/*
 ignore =
-    E126,  #continuation line over-indented for hanging indent
-    E127,  #continuation line over-indented for visual indent
-    E128,  #continuation line under-indented for visual indent
-    E201,  #whitespace after '{'
-    E202,  #whitespace before '}'
-    E225,  #missing whitespace around operator
-    E226,  #missing whitespace around arithmetic operator
-    E231,  #missing whitespace after ','
-    E241,  #multiple spaces after ','
-    E251,  #unexpected spaces around keyword / parameter equals
-    E252,  #missing whitespace around parameter equals
-    E261,  #at least two spaces before inline comment
-    E302,  #expected 2 blank lines,  found 1
-    E303,  #too many blank lines (2)
-    E305,  #expected 2 blank lines after class or function definition, found 0
-    E402,  #module level import not at top of file
-    E501,  #line too long (135 > 120 characters)
-    E502,  #the backslash is redundant between brackets
-    E722,  #do not use bare 'except'
-    E731,  #do not assign a lambda expression, use a def
-    F401,  #'typing.Dict' imported but unused
-    F403,  #'from catmaid.models import *' used; unable to detect undefined names
-    F405,  #'User' may be undefined, or defined from star imports: catmaid.fields, catmaid.models
-    F841,  #local variable 'ClientDatastore' is assigned to but never used
-    W503,  #line break before binary operator
-    W504,  #line break after binary operator
+    #continuation line over-indented for hanging indent
+    E126,
+    #continuation line over-indented for visual indent
+    E127,
+    #continuation line under-indented for visual indent
+    E128,
+    #whitespace after '{'
+    E201,
+    #whitespace before '}'
+    E202,
+    #missing whitespace around operator
+    E225,
+    #missing whitespace around arithmetic operator
+    E226,
+    #missing whitespace after ','
+    E231,
+    #multiple spaces after ','
+    E241,
+    #unexpected spaces around keyword / parameter equals
+    E251,
+    #missing whitespace around parameter equals
+    E252,
+    #at least two spaces before inline comment
+    E261,
+    #expected 2 blank lines,  found 1
+    E302,
+    #too many blank lines (2)
+    E303,
+    #expected 2 blank lines after class or function definition, found 0
+    E305,
+    #module level import not at top of file
+    E402,
+    #line too long (135 > 120 characters)
+    E501,
+    #the backslash is redundant between brackets
+    E502,
+    #do not use bare 'except'
+    E722,
+    #do not assign a lambda expression, use a def
+    E731,
+    #'typing.Dict' imported but unused
+    F401,
+    #'from catmaid.models import *' used; unable to detect undefined names
+    F403,
+    #'User' may be undefined, or defined from star imports: catmaid.fields, catmaid.models
+    F405,
+    #local variable 'ClientDatastore' is assigned to but never used
+    F841,
+    #line break before binary operator
+    W503,
+    #line break after binary operator
+    W504,