Replace Cobertura with JaCoCo code coverage reports

[seifertm]

The [https://github.com/valkolovos/gradle_cobertura/ Cobertura plugin for Gradle] is not officially supported. It is not actively developed, causes deprecation warnings and will stop working when Gradle 2.0 is released.

The best solution would be to use the [http://www.gradle.org/docs/current/userguide/jacoco_plugin.html JaCoCo plugin for Gradle.] JaCoCo is actively developed and its Gradle plugin is officially supported.

Imported from trac ticket 67, created by mseifert on 12-08-2013 at 13:38, last modified: 01-20-2014 at 16:28