Added documentation

sources.ini

@@ -0,0 +1,12 @@
+# Backup.py sample sources file
+# To backup new entries, add a mapping
+# of the time '<LABEL>=<PATH>'
+#
+
+# directories end with a slash...
+web_server=/var/www/
+ssh=/etc/ssh/
+
+# while individual files do not
+wireguard=/etc/wireguard/wg0.conf
+firewall=/etc/nftables.conf