Classes from current artifact are excluded when explicit shaded includes are provided

When specifying artifacts to include in shaded jar, the final jar seem to exclude the built classes for the current artifact. This is a change from 1.2.2 where the current artifact was (quite rightly) included (as you are not really shading it, but rather others into it).

Please find attached an example of this behaviour (example.zip);

$ mvn -DshadePlugin=1.2.2 clean package
$ unzip -l two/target/two-1-SNAPSHOT.jar | grep class
260 01-11-10 18:37 org/test/two/Two.class
317 01-11-10 18:37 shaded/org/test/one/One.class

$ mvn -DshadePlugin=1.3 clean package
$ unzip -l two/target/two-1-SNAPSHOT.jar | grep class
317 01-11-10 18:41 shaded/org/test/one/One.class