Added support for the Gradle run task to the helloworld example.
It is necessary to set run.standardInput so the app won't quit immediately.
Unfortunately, "gradle run" needs to be started with the -q switch. Otherwise the output gets garbled by Gradle output. This will be addressed in a future Gradle version.
Upgraded sampels helloworld gradle wrapper to Gradle 1.3.
Added and documented support for Gradle run task.
Execute 'gradlew -q run' to execute the run task.
-q is required to prevent garbled output.