CLOUD-2317 (Andy) : Implemented stubs for the 'to_query' calls which require ActiveSupport core extensions to be enabled in order to be used.  This allowed me to be able to refactor redirect_url and signout_url to both take advantage of the more Ruby-like way of doing things, while also removing code duplication.  I also added a new method signin_url which is more descriptive than redirect_url as to what it is returning.  redirect_url just calls into signin_url until we can remove it in the future.  I added spec coverage around both signin_url and redirect_url methods.