[Umlaut-general] new umlaut 3.x feature -- force new request, rather than cached request/response

[Jonathan Rochkind]

Added a new feature to umlaut 3.x latest alpha, that I've been wanting 
for a while. from the wiki:

https://github.com/team-umlaut/umlaut/wiki/Umlaut-URL-Parameters

## umlaut.force_new_request=true

Ordinarily, if a user with the same cookie-based sessionID requests the 
exact same OpenURL twice, the existing umlaut Request object will be 
re-used -- along with it's existing responses.  This is ordinarily a 
good idea -- it ensures that requests for background service updates 
hook up with the right request instead of creating a new one, and also 
in general makes more faster and more efficient responses with browser 
refresh, back button, or requesting the exact same umlaut page twice.

However, it can be inconvenient for development, when you need to 
re-execute a request to see how new versions of service plugins behave.  
It can also be a problem when a bug or problem in umlaut services has 
saved bad data, and users keep getting the bad data on re-request. While 
there's no general solution for the latter issue, individual people 
reporting the problem can be given a URL with 
"&umlaut.force_new_request=true" included to force a re-run of the 
request, not using cached Umlaut Request object.  This can also be used 
by developers.