Add remote listening cancelling

bc.lua

@@ -115,6 +115,8 @@ function bc:init(my_address, local_nouns, local_verbs)
         o.listening_remotes[message.noun] = o.listening_remotes[message.noun] or {}
         o.listening_remotes[message.noun][remoteAddress] = o.listening_remotes[message.noun][remoteAddress] or {}
         o.listening_remotes[message.noun][remoteAddress][message.id] = {query=message.query, qparam=message.qparam}
+      elseif message.ty == message_type.request_stop_listening then
+        o.listening_remotes[message.noun][remoteAddress][message.id] = nil
       elseif message.ty == message_type.listener_update then
         o.remote_listeners[message.noun][message.id].callback(o, message.value)
       end

test_bc.lua

@@ -80,12 +80,16 @@ function test_multinode_listening()
   i = false
   bc1:listen_cancel("foo", id) -- Test wether cancelling works
   local j = false
-  bc2:listen_noun("foo", "onchange", nil, function(bc, foo)
+  local rid = bc2:listen_noun("foo", "onchange", nil, function(bc, foo)
     j = true
   end)
   bc1:set_noun("foo", 1234)
   assert_true(j, "Remote listening failed")
-  assert_false(i, "Cancelling listener failed")
+  assert_false(i, "Cancelling local listener failed")
+  bc2:listen_cancel("foo", rid)
+  j = false
+  bc1:set_noun("foo", 34)
+  assert_false(j, "Cancelling remote listener failed")
 end
 
 function test_listen_modes()