Fixed a bug where the editor would exit because of a boost exception when browsing to a directory that the user does not have access to. The vfs now catches the boost exception and throws a FIFE exception. Updated the filebrowser to catch the exception and display a warning to the user. fixes[t:413]

<Panel title="Help">
	<ScrollArea min_size="300,400">
		<TextBox name="helpText"/>
	</ScrollArea>
	<Button name="closeButton" text="Close"/>
</Panel>