Collect engine-config and domain information

Currently sos/log-collector does not capture engine-config values or domain information.

We should capture both of these as the tunables can help in troubleshooting.
Similarly the domain information can help track AD/IPA issues.

These can currently dug out from the DB dump, however having them in a plaintext
file makes checking these much faster and easier, and a DB is not always available.

Change-Id: I1c5d715e6584c7624139bbfb4304ffdc40c4e7dc
Bug-Url: https://bugzilla.redhat.com/1173766
Signed-off-by: Jake Hunsaker <jhunsaker@redhat.com>