Update empty.sh, trap.sh files

empty.sh

+#! /usr/bin/env sh
+
+DEST=${AWS_S3_MOUNT:-/opt/s3fs/bucket}
+. trap.sh
+
+tail -f /dev/null

trap.sh

+exit_script() {
+    SIGNAL=$1
+    echo "Caught $SIGNAL! Unmounting ${DEST}..."
+    fusermount -uz ${DEST}
+    s3fs=$(ps -o pid= -o comm= | grep s3fs | sed -E 's/\s*(\d+)\s+.*/\1/g')
+    if [ -n "$s3fs" ]; then
+        echo "Forwarding $SIGNAL to $s3fs"
+        kill -$SIGNAL $s3fs
+    fi
+    trap - $SIGNAL # clear the trap
+    exit $?
+}
+
+trap "exit_script INT" INT
+trap "exit_script TERM" TERM