Flake8 configuration in tox.ini

Hi,

I just started to explore the fastai codebase and was thinking to contribute here and there. I configured my flake8 to adhere to the fastai coding style. Would it be useful to add this to the tox.ini file such that flake8 will be automatically configured?

I was thinking of something like this:

[flake8]
ignore =
    # F403 	‘from module import *’ used; unable to detect undefined names
    F403,
    # F405 	name may be undefined, or defined from star imports: module
    F405,
    # E226 	missing whitespace around arithmetic operator
    E226,
    # E231 	missing whitespace after ‘,’, ‘;’, or ‘:’
    E231,
    # E241 	multiple spaces after ‘,’
    E241,
    # E275 	missing whitespace after keyword
    E275,
    # E302 	expected 2 blank lines, found 0
    E302,
    # E305 	expected 2 blank lines after end of function or class
    E305,
    # E401 	multiple imports on one line
    E401,
    # E701 	multiple statements on one line (colon)
    E701,
    # E704 	multiple statements on one line (def)
    E704
max-line-length = 160