Xtend support

[AlexandreRio]

I'm using Xtend (http://www.eclipse.org/xtend/) programming language in my java projects.
I tried to use Eclim features on it just to see if it works and it doesn't (pretty obvious).

I just run set ft=java in vim and then tried the completion command and I have the following error

  [org.eclim.command.Main] Command failed
java.lang.IllegalArgumentException: Compilation unit name must end with .java, or one of the registered Java-like extensions

I know vim doesn't really support xtend (I can't find a working colorscheme).

How hard would it be to support xtend language?