mod_roster_command: Fix subscription when the "user JID" is a bare domain. Do not attempt to update the roster when the user is bare domain (e.g. a component), since they don't have rosters and the attempt results in an error: $ prosodyctl mod_roster_command subscribe proxy.example.com contact@example.com xxxxxxxxxxFailed to execute command: Error: /usr/lib/prosody/core/rostermanager.lua:104: attempt to concatenate local 'username' (a nil value) stack traceback: /usr/lib/prosody/core/rostermanager.lua:104: in function 'load_roster' /usr/lib/prosody/core/rostermanager.lua:305: in function 'set_contact_pending_out' mod_roster_command.lua:44: in function 'subscribe'

<div id="title">
	<div id="date">###DATE###</div>
	<div id="roomjid">###JID###</div>
	<div id="links">(join via <a class="component" href="xmpp:###JID###?join">client</a>)</div>
</div>
<div id="calendar">
	<div id="navigation">
		###PREVIOUS_LINK### <a class="nav" href="../">^</a>###NEXT_LINK###
	</div>
	###CALENDAR###
</div>
<div id="topic">###TITLE_STUFF###</div>
<br />
<input id="toggleUTC" type="checkbox" onclick="changeTimeDisplay()" /><label for="toggleUTC">show time in local time, rather than in UTC</label>
<div id="main">###DAY_STUFF###</div>