runClasspathExcludes seems to be disregarded

I'm using the `org.codehaus.mojo.gwt-maven-plugin` plugin in version `2.8.2`.

This is my configuration:

```xml

com.mycompany.myproject.gwt.App
-Xmx2G
app

storm-core-1.0.1.jar

```

the interesting part is the `runClasspathExclude`. When I run GWT Development Mode, the jar is *not* excluded from the war classpath :(.

This makes the JAR appear twice on the classpath which is something that it explicitly guards against:

> Found multiple defaults.yaml resources. You're probably bundling the Storm jars with your topology jar.
> [jar:file:/C:/Data/Maven%20Repository/org/apache/storm/storm-core/1.0.1/storm-core-1.0.1.jar!/defaults.yaml, jar:file:/C:/Git/myproject/myproject-ui/target/myproject-ui-2.0.5-SNAPSHOT/WEB-INF/lib/storm-core-1.0.1.jar!/defaults.yaml]

Is there any workaround I can do to exclude the jar?

Start by reproducing GWT Development Mode with the shown org.codehaus.mojo.gwt-maven-plugin 2.8.2 configuration and inspect how runClasspathExcludes is applied to the war classpath. Done means storm-core-1.0.1.jar is excluded and the duplicate defaults.yaml warning no longer appears.

Written by the indexing model from the issue text.