Correct Cobertura and PMD classpath.

Change-Id: I1bbf6cfb8d05c7777692f623535f3edcc184c71a
Add includeantruntime="false" to javac tasks. Delete commented fileset
entrier.

Change-Id: I886adfad51744ec4720f8db1e35f94ba4602b173
Add ant contrib namespace.

Change-Id: I83eab5b2f30c27a381426d7b9cb93ac8fde9b040
Align PMD Ant task wit 5.0 version of PMD.