gwt-dev provided dependency should ignore transitive dependencies

[gopf]

The plugin installs gwt-dev as a providedCompile dependency, but this also excludes all of the transitive dependencies by default. We need commons-codec in our project but this isn't included in the WAR file (transitive dependency of gwt-dev).

When adding the gwt-dev dependency, could you set the transitive = false option?

[esocode]

Changing such a fundamental behavior could cause side effects for other user of the plugin, therefore such a change would probably need to be implemented as an optional feature. I'm currently not working on GWT projects and are quite busy, so I'm not able to add features on this plugin. But feel free to provide a PR.