run_tests: add checks suite
run_tests: add checks suite

For now this just runs pyflakes and pep8 for pwcli. Need to extend it later.

Signed-off-by: Kalle Valo <7081a7d99b8c74c0698a728df19e3915a995d7e1@codeaurora.org>

kvalo/pwcli,kvalo/pwcli