facts: recreate the choices experience in facts

recreates the choices view in facts, allowing for display of any fact
category in the system, and providing a random item from it

bss/dr.botzo#15

dr_botzo/urls.py

@@ -14,6 +14,7 @@ urlpatterns = [
 
     url(r'^choices/', include('choices.urls')),
     url(r'^dispatch/', include('dispatch.urls')),
+    url(r'^itemsets/', include('facts.urls')),
     url(r'^karma/', include('karma.urls')),
     url(r'^markov/', include('markov.urls')),
     url(r'^races/', include('races.urls')),