Find a way to pass arguments to flynt call

[jedie]

Sadly "flynt" didn't has any config file, see: ikamensh/flynt#111

If a project needs to exclude some directory, than it has to define a own do_linting() function to change:

dev-shell/dev_shell/command_sets/dev_shell_commands.py

Line 26 in 15e752e

'flynt', '--fail-on-change', '--line_length=119', '.',

Find a way to pass arguments to flynt call