Migrate to cobertura-maven-plugin 2.5.1 (= Cobertura 1.9.4.1) from 2.2 (= Cobertura 1.9).

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/compress/trunk@1189253 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/pom.xml b/pom.xml
index 5c67c6a..438bda2 100644
--- a/pom.xml
+++ b/pom.xml
@@ -177,7 +177,7 @@
         <!-- generate a code coverage report -->
         <groupId>org.codehaus.mojo</groupId>
         <artifactId>cobertura-maven-plugin</artifactId>
-        <version>2.2</version>
+        <version>2.5.1</version>
       </plugin>
       <plugin>
         <!-- generate the PMD reports -->