Revert "unbound: Deactivate qname-minimization & harden-below-nxdomain"

This reverts commit 86e9d04bfb.

This seems to be working with unbound 1.6.0 so that this can be
re-enabled for better privacy.

http://lists.ipfire.org/pipermail/development/2016-December/002807.html

config/unbound/unbound.conf

@@ -42,6 +42,7 @@ server:
 	# Privacy Options
 	hide-identity: yes
 	hide-version: yes
+	qname-minimisation: yes
 	minimal-responses: yes
 
 	# DNSSEC
@@ -55,6 +56,7 @@ server:
 	harden-short-bufsize: no
 	harden-large-queries: yes
 	harden-dnssec-stripped: yes
+	harden-below-nxdomain: yes
 	harden-referral-path: yes
 	harden-algo-downgrade: no
 	use-caps-for-id: no