Refactoring to support collecting scm stats for different periods.
Computation of metrics for three different periods
Adding widget properties and new terms for localization
Change parent pom to version 16
add CVS support
Merge pull request #3 from bsavelev/master

CVS support
Change no data message to explain the user what might have been wrong.
Show only top 10 authors in authors activity 
Store commits per user sorted by total commits of users by descending order
Minor messages improvements
Implement equals in Comparator to avoid compile failing in JDK 5
Remove @Override annotations for Java 1.5 compatibility
[maven-release-plugin] prepare release sonar-scm-stats-plugin-0.2
[maven-release-plugin] prepare for next development iteration