migrate the MXJ to MariaDB4j

The MXJ project has died, so the standalone build would probably need to be migrated to using MariaDB4J.

This consist of changing this dependency 

</dependency>

by
<dependency>
<groupId>ch.vorburger.mariaDB4j</groupId>
<artifactId>mariaDB4j</artifactId>
<version>2.4.0</version>
<scope>test</scope>
</dependency>

Since Travis doesn't test this by default,  you have to run the integration test  with the command: mvn clean test -Pskip-default-test -Pintegration-test you computer .