Help user on Nuxeo nature activation (Seam, WebEngine, ...)

When activating the Nuxeo nature on an existing project, some files (Seam, WebEngine resources, ...) need to be refactored or added to the buid PATH.
It would be nice the give information to the user and help him as much as possible into properly reorganizing his project and configuring the project settings.

Here's a feedback from EasySOA developers:
<< When a project is converted into a Nuxeo project, the WebEngine resources won't be deployed because the skin has to be manually included in the build path.
Q: WebEngine modules templates are not deployed (org.nuxeo.ecm.webengine.model.TemplateNotFoundException: Template XXX.ftl not found
A: The project's skin is probably not deployed, because unless the WebEngine project has been generated by the Nuxeo plugin, you have to include it manually in the build path. To solve this, right click the skin/ folder, then choose Build Path > Include. >>

There could be a detection of potential WebEngine resources. About Seam, it's more complicated but the plugin has to give some information and guidance to the user.