Added better description to the exmaple config file.

dns-update.conf

@@ -1,3 +1,16 @@
-# ip_protocol	hostname	password
+# Dynamic DNS record configuration file for Hurricane Electric Free DNS service.
+#
+# Everything starting with a pound sign (#) is considered as comment and discarded.
+# Each line describes a single dynamic DNS entry that you set up at HE.
+# Each entry consists of 3 columns, separated with any number and kind of whitespace.
+#
+#/-------- IP protocol version: 4 (for A records) or 6 (for AAAA records)
+#|  /----- Fully qualified hostname of the entry
+#|  |  /-- The key for the dynamic DNS entry.
+#|  |  |  
+#|  |  \----------------\
+#|  |                   |  
+#v  v                   v
+
 4	test.example.org	foobarbazqux
 6	ipv6.example.org	abcdef123456

dns-update.sh

@@ -5,7 +5,6 @@
 #
 # (c) Peter Budai, 2018
 # https://peterbudai.eu/
-#
 
 # Global variables
 # Full path to the executing script file