Update Readme with version details and gist tag

Author: Muharrem Tigdemir

Dockerfile

@@ -1,5 +1,5 @@
 
-FROM php:7.1-cli-alpine
+FROM php:7.3.25-cli-alpine
 
 ## Install SSH and Rsync
 RUN apk add --no-cache openssh rsync
@@ -12,4 +12,4 @@ RUN composer global require deployer/deployer
 RUN composer global require deployer/recipes --dev
 
 ## Add Composer vendor into PATH
-ENV PATH /root/.composer/vendor/bin:$PATH
+ENV PATH /root/.composer/vendor/bin:$PATH

README.md

@@ -5,6 +5,14 @@ Please have a look at this article to find out how to use Deployer with self-bui
 https://medium.com/@mtigdemir/php-deployment-with-deployer-to-aws-via-bitbucket-pipeline-a605763c63bf
 
 
-## Example Bitbucket Pipeline 
+## How to use Deployer Image with Bitbucket Pipeline 
 
-<script src="https://gist.github.com/mtigdemir/1bb599d7fa5caad3ab647aad87fadc18.js"></script>
+### Available Versions
+
+- PHP 7.1 (`mtigdemir\php-deployer-pipeline:7.1`)
+- PHP 7.3 (`mtigdemir\php-deployer-pipeline:7.3.25`)
+
+{% gist 1bb599d7fa5caad3ab647aad87fadc18 %}
+
+
+Please note that, only PHP 7.1 tag uses Composer v1 and all the builds after that compatible with Composer v2