remove modules that cannot be instantiated

Author: Brent Cook

lib/msf/core/module_set.rb

@@ -57,6 +57,8 @@ def create(reference_name)
     # Notify any general subscribers of the creation event
     if instance
       self.framework.events.on_module_created(instance)
+    else
+      self.delete(reference_name)
     end
 
     return instance