Allow to configure the filteredExtentions from the archetype.properties file

The project I'm using to generate archetype has HTML that use "#end" as CSS selector.
I have to set custom filteredExtentions to avoid this.

• Using extension-based file selection is not fine-grained. Using some Ant expression for includes/excludes would be more configurable.
• As my project is used to build archetypes, it includes an archetype.properties file in SVN. I'd like include the filteredExtentions in it, but simply adding archetype.filteredExtentions=java,xml,txt,groovy,jsp,gsp,vm,properties has no effect on my issue. It seems using "-Darchetype.filteredExtentions=..." is required. Ability to configure ALL the archetype generation in archetype.properties would be cleaner.