Add support for multiple cron jobs within rsync client

Readme.md

@@ -19,10 +19,11 @@ Get files from `remote server` to a `data container`:
 
 ### Client setup
 
-Start client to sync every night at 3AM:
+Start client to pack and sync every night:
 
     $ docker run --name=rsync_client -v client_vol_to_sync:/data \
-                 -e CRON_TASK="0 3 * * * rsync -e 'ssh -p 2222 -o StrictHostKeyChecking=no' -avz root@foo.bar.com:/data/ /data/" \
+                 -e CRON_TASK_1="0 1 * * * /data/pack-db.sh" \
+                 -e CRON_TASK_2="0 3 * * * rsync -e 'ssh -p 2222 -o StrictHostKeyChecking=no' -avz root@foo.bar.com:/data/ /data/" \
              eeacms/rsync client
 
 Copy the client SSH public key printed found in console

docker-entrypoint.sh

@@ -13,10 +13,16 @@ if [ ! -z "$SSH_AUTH_KEY" ]; then
 fi
 
 # Provide CRON_TASK via environment variable
-if [ ! -z "$CRON_TASK" ]; then
-  echo "$CRON_TASK" > /etc/crontabs/root
+echo '' > /etc/crontabs/root
+for item in `env`; do
+   case "$item" in
+       CRON_TASK*)
+            ENVVAR=`echo $item | cut -d \= -f 1`
+            printenv $ENVVAR >> /etc/crontabs/root
             echo "root" > /etc/crontabs/cron.update
-fi
+            ;;
+   esac
+done
 
 # Generate host SSH keys
 if [ ! -e /etc/ssh/ssh_host_rsa_key.pub ]; then