Add missing newline in documentation code example

Author: nicki-krizek

doc/arm/zones.inc.rst

@@ -460,6 +460,7 @@ This example generates A and AAAA records using modifiers; the AAAA
 is equivalent to:
 
 ::
+
    HOST-0000.EXAMPLE.   A      1.2.3.1
    HOST-0001.EXAMPLE.   A      1.2.3.2
    HOST-0002.EXAMPLE.   A      1.2.3.3