README.md updated

README.md

 # seqr-prestashop-data
 Docker data container for prestashop
+
+## How to run this
+Mapping local plugin dev directory to the Prestashop data container.
+
+```bash  
+export DEV_DIR /home/yourhome/path/to/seqr/plugin
+
+docker-compose up
+
+```
+
+Your Prestashop site will be available on the **8080** port.
+
+## Available ports
+ * 8080: Prestashop site
+ * 3306: mysql database
+ * 9000: Xdebug extension for PHP debugging
+
+## Prestashop database
+
+  username: **root**
+
+  password: