
Sample SendDisplayManialinkPage() :

<manialinks>
	<manialink posx="" posy ="" id="">
		....
	</manialink>
	<manialink posx="" posy ="" id="">
		....
	</manialink>
	<custom_ui>
		<notice visible="true"/>
		<challenge_info visible="true"/>
		<chat visible="true"/>
		<checkpoint_list visible="true"/>
		<round_scores visible="true"/>
		<scoretable visible="true"/>
		<global visible="true"/>
	</custom_ui>
</manialinks>


when a new Manialink page is received:
previously displayed <manialink> with the same id as one in the new page are replaced.
previously displayed <manialink> without an id are deleted
previously displayed <manialink> with an id are kept.
a new empty <manialink> with an id means delete the previously displayed <manialink> with this id.

<custom_ui> stays unchanged if not specified.
if no pages are displayed, the <custom_ui> returns to the default "all visibles".

