Fixed routed messages

It might be not initialized in some cases

```
NoMethodError: undefined method `<<' for nil:NilClass
    /Users/igoryamolov/.rbenv/versions/2.0.0-p247/lib/ruby/gems/2.0.0/gems/stuffed_bunny-1.0.0/lib/stuffed_bunny/bunny_overrides.rb:63:in `publish'
```