Added wait-cluster script

scripts/wait-cluster.sh

@@ -0,0 +1,19 @@
+#!/bin/bash
+
+attempt_counter=0
+max_attempts=5
+url='http://localhost:9200/_cluster/health?wait_for_status=green&timeout=50s'
+
+echo "Waiting for Elasticsearch..."
+while [[ "$(curl -s -o /dev/null -w ''%{http_code}'' --max-time 55 "$url")" != "200" ]]; do
+  if [ ${attempt_counter} -eq ${max_attempts} ];then
+    echo "\nCouldn't connect to Elasticsearch"
+    exit 1
+  fi
+
+  printf '.'
+  attempt_counter=$(($attempt_counter+1))
+  sleep 5
+done
+
+echo "\nReady"