Route: Fixed handling of object parameters

Sometimes I use objects as parameters. A nice way to deal with them is to put them into another object using this class: https://gist.github.com/enumag/1f98ce3beffa2490c6ca.

Using this the object will be converted to it's identifier unless I do something else with it in the FILTER_OUT function. First way is useful in AdminModule because I don't care about pretty urls there. Second way is handy for FrontModule because I can slugify the object in FILTER_OUT.

This works fine if the parameter is mentioned in the route string directly. If it isn't it should appear in the query string - and this is the the bug. The parameter disappears instead because the `http_build_query` function ignores objects completely (even if they have a __toString function declared).