Add listing of env variables to use

README.md

@@ -10,8 +10,35 @@ Just start the class DemoServer
 
 ### Executable JAR file
 1. Open a terminal window
-3. Change directory to your project location
+2. Change directory to your project location
 3. Run `gradlew publishToMavenLocal`
 4. Change directory to build/libs
-4. Run `java -jar demo-server-0.1.0-BUILD-SNAPSHOT.jar`
+5. Run `java -jar demo-server-0.1.0-BUILD-SNAPSHOT.jar`
 
+#### Supported Environment Variables
+
+Sample usage: `java -jar -Ddemoserver.persistent=true demo-server-0.1.0-BUILD-SNAPSHOT.jar`
+
+##### demoserver.persistent (true/false)
+Run in persistent mode and to NOT use embedded datastores
+
+##### demoserver.provision (true/false)
+Run the provision steps against the services to bootstrap tenants
+
+##### custom.cassandra.contactPoints
+Custom cassandra contact points (multiple values allowed separated by comma e.g. 127.0.0.1:9042,127.0.0.2:9042)
+
+##### cassandra.cluster.user
+cassandra user to use
+
+##### cassandra.cluster.pwd
+cassandra password to use
+
+##### custom.mariadb.host
+mariadb host to use
+
+##### custom.mariadb.user
+mariadb user to use
+
+##### custom.mariadb.password
+mariadb password to use