add memcached configuration option, small corrections for the build process and add installDrupal.sh file to the release
---
.travis.yml:
forge_password: "ASTRdmLjJNa1NvHy2LRGvmvUeth6W3Fh/alYWvcvI8nDDsdkweHk0iXhcXZwtMQReb0NI5vJiRNXNy7a3XySC4+SP3hfHuDU58H2FqC4Ff0EHRPRHTEiXf7xmN53RxXYXZQvrFfqUb6tIsBNVKVmsYWNe01k8NVKPyYDfQB75PQ="