[Gradle Release Plugin] - pre tag commit:  '0.2.1'.
[Gradle Release Plugin] - new version commit:  '0.2.2-SNAPSHOT'.
Change travis to use jdk6
Change source compatibility to 1.6
[Gradle Release Plugin] - pre tag commit:  '0.2.2'.
[Gradle Release Plugin] - new version commit:  '0.2.3-SNAPSHOT'.
Set convertJavacard as dependency of build tasks
[Gradle Release Plugin] - pre tag commit:  '0.2.3'.
[Gradle Release Plugin] - new version commit:  '0.2.4-SNAPSHOT'.
Update Readme with more details for setup