Extracted route path variables should be injected into request params

[erdi]

Currently if you want to pass path variables extracted in route evaluation you have to add them as part of the query string of the route destination. This is cumbersome and could be made much simpler by putting extracted path variables values in request params, let's say under pathVariables. This should be pretty simple as the request is available in the place in code where path variables are extracted (https://github.com/gaelyk/gaelyk/blob/master/core/src/main/groovyx/gaelyk/routes/Route.groovy#L122)