Enable marconi-server to run when USE_SCREEN=false

This patch,
1. adds log_file option to marconi.conf
2. redirects the output from marconi-server, in the same precedent
set by another project.

Change-Id: Ib273a03625d5a4edf8bb3ed7d522d2b087975acd
put libvirt debug in the right place

libvirt debug setting was happening in a place where we weren't
actually resetting the daemon. Move it to into the hypervisor
plugin where we do.

Change-Id: Ia79b0ef50f6b8fb007a20ce5cb4e510a5e4600a5
Configuration needed for neutron nova callback

Change-Id: I07cb476f5e87e967cd6fbbfc82881e8a147453b4
Merge "Enable marconi-server to run when USE_SCREEN=false"
Merge "put libvirt debug in the right place"
Merge "Configuration needed for neutron nova callback"
Merge branch 'master' of https://github.com/openstack-dev/devstack