Add configuration defaults

Don't depend on update.cfg being there.

Move existing hard-coded config to example config.

update.cfg.example

@@ -0,0 +1,16 @@
+# vi: ft=sh
+# Defaults:
+#WORKDIR=${WORKDIR:-${BASH_SOURCE%/*}}
+#BACKUPSUFFIX=
+#BLOCKLIST=$WORKDIR/block.list
+#LIST_DIR=$WORKDIR/lists
+#OUT=()
+#URL=()
+
+# Individual hosts lists in that collection
+#OUT+=("$LIST_DIR/sb-Badd-Boyz-Hosts.hosts")
+#URL+=('https://raw.githubusercontent.com/StevenBlack/hosts/master/data/Badd-Boyz-Hosts/hosts')
+
+# Not sure how I'm supposed to update this file...
+#OUT+=("$LIST_DIR/list.1.raw.githubusercontent.com.domains")
+#URL+=('???')