Add configuration defaults

Don't depend on update.cfg being there.

Move existing hard-coded config to example config.

update.cfg.example

@@ -1,10 +1,11 @@
 # vi: ft=sh
-WORKDIR=${WORKDIR:-${BASH_SOURCE%/*}}
-BACKUPSUFFIX=.old
-BLOCKLIST=$WORKDIR/block.list
-LIST_DIR=$WORKDIR/lists
-OUT=()
-URL=()
+# 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")

update.sh

@@ -6,7 +6,15 @@ set -e
 WORKDIR=${0%/*}
 CFG=$WORKDIR/update.cfg
 
-. "$CFG"
+# Config defaults
+BACKUPSUFFIX=
+BLOCKLIST=$WORKDIR/block.list
+LIST_DIR=$WORKDIR/lists
+OUT=()
+URL=()
+if [[ -f $CFG ]]; then
+    . "$CFG"
+fi
 
 TEMP_DIR=$(mktemp -d -t "${0##*/}.XXXXXX")
 cleanup() {