webapp-cache.xml schema available online

When packaging a web-application, maven-war-plugin generates a cache file, as described here: http://maven.apache.org/plugins/maven-war-plugin/exploded-mojo.html#cacheFile

This cache file is an XML file but the generated file doesn't contains an Schema or DTD declaration on its header. This makes impossible to validate such file, generating warnings in the most common Java IDEs.

Since it is an XML file I believe it should has a model specification somewhere (a XSD Schema I hope), eventually just not released for public usage.

So, please publish the XSD Schema (or dtd) of the cache file in order to give the developers a chance to detect potential bugs before to deploy their web-application.