Enable pep8 + pylint gating.

In order to avoid simple mistakes in anvil it is
pretty useful to enable the basic sets of style
and sanity checks that pep8 and pylint can provide.

Change-Id: I97e742838d92bb099368f818a76e2374e297bc52
Fixes: bug #1196623
Reviewed-on: https://review.openstack.org/35167
Reviewed-by: James E. Blair <corvus@inaugust.com>
Reviewed-by: Monty Taylor <mordred@inaugust.com>
Reviewed-by: Jeremy Stanley <fungi@yuggoth.org>
Approved: Clark Boylan <clark.boylan@gmail.com>
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Tested-by: Jenkins