Substituting redfish-emulator and reverse-proxy with Apache

The current implementation of airship-libvirt-gate is using
sushy-emulator binary to emulate redfish. Sushy-emulator works
only for http and also can’t authenticate users out-of-box if
ran by itself. In order to check https and authentication the
reverse-proxy was introduced. This approach had several
drawbacks:
1) http still doesn’t check auth
2) to use apache for https only is too heavy solution for https
This change converts reverse proxy to apache running
sushy-emulator as wsgi backend, that gives an ability to check
authentication for both http and https.
We’re also getting rid of ad-hoc sushy-emulator service and
using out-of-box apache service implementation.
The code also introduces gathering of apache resulting configs
and logs for quicker debug if needed.
Right now authentication is disabled, since manifests are
written in a way so they don’t use them. If it’s necessary to
enable it, just set username here[1]

PS
There is ability to use apache for http-server [2], but it’s
better to do as a separate PR

[1]
roles/airship-libvirt-gate/defaults/main.yaml
[2]
roles/http-fileserver

Change-Id: I43b5bca41519c88b01535c156b2db0e9edaa81bb

playbooks/airship-collect-logs.yaml

@@ -17,7 +17,7 @@
     logs_dir: "/tmp/logs"
   roles:
     - gather-system-logs
-    - airship-gather-sushy-logs
+    - airship-gather-apache-logs
     - airship-gather-libvirt-logs
     - airship-gather-runtime-logs
     - airship-airshipctl-gather-configs