moduleapi: Use multitable add/remove instead of set multitable:set() does not clear intermediate keys when setting the last one to nil. This meant that the event_handlers multitable for every module was not properly cleaning up the object and event name from the table when calling :unhook_object_event(). This combined badly with e.g. mod_bookmarks, which uses this extensively to add/remove hooks dynamically for mod_pep services. The multitable kept a reference to every mod_pep service object ever created, causing a memory leak. The multitable:remove() function clears intermediate keys when they are empty, so we've switched to using that now.

-- XEP-0307: Unique Room Names for Multi-User Chat
local st = require "util.stanza";
local unique_name = require "util.id".medium;
module:add_feature "http://jabber.org/protocol/muc#unique"
module:hook("iq-get/host/http://jabber.org/protocol/muc#unique:unique", function(event)
	local origin, stanza = event.origin, event.stanza;
	origin.send(st.reply(stanza)
		:tag("unique", {xmlns = "http://jabber.org/protocol/muc#unique"})
		:text(unique_name():lower())
	);
	return true;
end,-1);