Fix Swift process kill

stop_swift() was not killing all swift processes properly.  Change to
manually clean up all screen services with pkill.

Closes-bug: 1268794
Change-Id: Ibb7a2e0dd10a313609f05963264087f82f6f00e2
Clean up Neutron service checks

Add is_neutron_enabled() to lib/neutron to enable removing the 'neutron'
special-case in the is_service_enabled() function itself.

TODO: remove the neutron test from is_service_enabled() after a transition period

Change-Id: I2852e2d0b8b121f3c402c2d8fc4f6359d95d00ca
Merge branch 'trove-plugin' into dt-test
Merge branch 'code-cleanup' into dt-test
Merge branch 'enabled-base' into dt-test
Merge branch 'enabled-cinder' into dt-test
Merge branch 'enabled-glance' into dt-test
Merge branch 'enabled-neutron' into dt-test
Merge branch 'enabled-nova' into dt-test
Merge branch 'enabled-swift' into dt-test
Merge branch 'enabled-ceilometer' into dt-test