un-ignore flake8 E226, E242, E704

none of these required any code changes

setup.cfg

@@ -9,11 +9,8 @@ ignore =
     E123,  # closing bracket does not match indentation of opening bracket's line
     E126,  # continuation line over-indented for hangin indent
     E221,  # multiple spaces before operator (for vertical alignment)
-    E226,  # missing whitespace around arithmetic operator
     E241,  # multiple spaces after non-arithmetic operators (for vertical alignment)
-    E242,  # tabs after ','
     E305,  # expected 2 blank lines after end of function or class
-    E704,  # multiple statements on one line
     E731,  # do not assign a lamba expression, use a def
     E741,  # do not use variables name 'I', 'O', or 'l'
     # pycodestyle warnings