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="Elevation Editor">
	<HBox>
		<VBox name="Metadata Properties">
		</VBox>
		<VBox>
			<Button name="layerButton" text="Edit Layer"/>
			<Spacer /> 		
			<Button name="closeButton" text="Close"/>
		</VBox>
	</HBox>
</Panel>