Generic .uri suffix to get the URI representation of any file property

It's impossible to properly generate, for instance, a java policy file which needs files URIs, using either Cargo properties and filtered config files, or just filtered resources.

In both cases, the problem is the impossibility to generate proper URIs when expanding Maven properties (see also MNG-3760).

The candidate feature is to add a way to explicitly request the URI when expanding a property by means of a .uri suffix. The underlying getUri() method should rely on the correct Path#toUri() and neither File#toUri() nor File#toString(), see the SO reference in MNG-6386.

For instance:

• ${project.basedir.uri} instead of the broken ${project.baseUri} (and of course fix MNG-6436 otherwise it's useless)
• ${project.build.directory.uri}
• ${settings.localRepository.uri}
• etc