mod_stream_management: fix nasty session leak, fitting this in 3.1 as…

… it must be. (Fixes #43)

plugins/mod_stream_management.lua

@@ -107,10 +107,10 @@ local function wrap(session, _r) -- SM session wrapper
 
 	local close = session.close;
 	function session.close(...)
-		local token = session.sm_token;
+		local token = session.token;
 		if token then
 			handled_sessions[token] = nil;
-			session.sm_token = nil;
+			session.token = nil;
 		end
 		return close(...);
 	end
@@ -277,7 +277,6 @@ end);
 
 module:hook("pre-resource-unbind", function(event)
 	local session, _error = event.session, event.error;
-	if session.halted then return true; end
 	if session.sm then
 		if session.token then
 			session.log("debug", "Session is being halted for up to %d seconds", timeout);