Disable some pylint checks
Disable some pylint checks

Newer pylint added some checks that trigger a lot for this
code base. Turn them off until we are ready to apply the
new rules.  They are:

 - c-extension-no-member (Informational)
 - keyword-arg-before-vararg (Warning)
 - inconsistent-return-statements (Refactor recommendation)

Change-Id: I8c1f72bb334c87d62d47e8296d13c660d6bb5576
Signed-off-by: Doug Hellmann <0798ebecfb7bc4dfb9d0445c2fa030eb64e1fa1c@doughellmann.com>

mahak/neutron,openstack/neutron,noironetworks/neutron,mahak/neutron,openstack/neutron,noironetworks/neutron,openstack/neutron,mahak/neutron