Add script to launch a `nailgun` server.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>

Formula/nailgun.rb

@@ -5,8 +5,16 @@ class Nailgun <Formula
   homepage 'http://martiansoftware.com/nailgun/index.html'
   md5 '79365e339275d774b7c5c8b17b7ece40'
 
+  def script
+    <<-EOS
+#!/bin/bash
+exec java -server -jar "#{prefix}/nailgun-0.7.1.jar"
+    EOS
+  end
+
   def install
     system "make"
+    (bin+'ng-server').write script
     bin.install 'ng'
     prefix.install 'nailgun-0.7.1.jar'
   end