new frontend written in D

[Trass3r]

> But this example shows the path:
> Imho a new frontend would need to focus on non-compiler applications  
> first, such as
> - auto-completion etc. for IDEs
> - rewriting tools
> (- doc generation)
>
> cause these don't require a full-blown semantic analysis and codegen.

I think this strategy would also enforce a proper design since  
requirements are much firmer especially in the IDE context,
e.g. performance, memory usage, no stdout, exception safety, ...