1153344 - Allow Mongo connections over SSL.

https://bugzilla.redhat.com/show_bug.cgi?id=1153344
If these are left blank then it's inconsistent with the [messaging] and [tasks] section. Those sections don't contain blank defaults for the same reason this one shouldn't. We have a script that creates self-signed serts that align with the default. We could introduce something similar to that in the future, at which point a default would be good.

Also, there is a consistency argument in favor of defaults so that it is consistent with the [messaging] and [tasks] sections. It would be strange for us to not be consistent and apple the same thinking with the same settings for different components in the same file.