Revise consensus-flavors proposal to better URLs.

The old flavored consensus URL format made it harder to decode URLs
based on their prefixes, and didn't take into account our "only give
it to me if it's signed by enough authorities" stuff.

doc/spec/proposals/162-consensus-flavors.txt

@@ -72,9 +72,11 @@ Spec modifications:
    design.
 
    In addition to the consensus currently served at
-   /tor/status-vote/(current|next)/consensus.z , authorities serve
+   /tor/status-vote/(current|next)/consensus.z  and
-   another consensus of each flavor "F" from the location
+   /tor/status-vote/(current|next)/consensus/<FP1>+<FP2>+<FP3>+....z ,
-   /tor/status-vote/(current|next)/F/consensus.z.
+   authorities serve another consensus of each flavor "F" from the
+   locations /tor/status-vote/(current|next)/consensus-F.z. and
+   /tor/status-vote/(current|next)/consensus-F/<FP1>+....z.
 
    When caches serve these documents, they do so from the same
    locations.