Added ability to define argument value type.
Until now it was only possible to fetch text values, now you can define the argument value to be either text, integer, decimal, list,... and use the variable to e.g. fetch an enitiy by it's ID.
Note that since alpha8, paths aren't sorted by default but you may enable doing so using the admin config page. Sorted paths lead to unique, canonical urls. Keep in mind that this will replace the order in which user clicked the facets.