Identify origination of requests

In order to determine based upon the request whether to honor the request, or whether the request should be restricted, the request needs to identify itself in some way. Some of the requests in the system originate as a result of direct user requests (e.g. makeRequest) while other requests are performed by the server for the server or in order to handle the request (e.g. gadget spec lookups).

The proposal is to better mark the origination of the request either by attaching an Anonymous Security Token containing the gadget URI, or by marking the request as an internal request (one that the server is initiating) so that downstream components (e.g. the HttpFetcher implementation) can make determinations on how to process the request.