Abstract classes to manage report generation, which can be run both:
Creating a new report plugin can be done by copying AbstractMavenReportTest.java structure and implement a few methods.
Until Maven 2.0.4, maven-reporting-impl was included in Maven 2 core distribution: version used was completely driven by Maven version used.
The module was removed from Maven core starting with Maven 2.0.5 and moved to shared components to improve fexibility: starting with Maven 2.0.5, each plugin can choose its maven-reporting-impl version independently from Maven.