Module xml load incorrect

[mreishman]

Currently for more than one module in the header, layout is

<header>
	<module>
		<name>header</name>
		<enabled>true</enabled>
	</module>
</header>
<header>
	<module>
		<name>backToTopButton</name>
		<enabled>true</enabled>
	</module>
</header>

should be

<header>
	<module>
		<name>header</name>
		<enabled>true</enabled>
	</module>
	<module>
		<name>backToTopButton</name>
		<enabled>true</enabled>
	</module>
</header>