Add Full Screen Option in Display Options

[tyrelius]

Add the full screen option in the section for display options. Example is below.

<?xml version="1.0" encoding="UTF-8"?>
<objects name="Object Load" version="0.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
	<object type="SystemOptions" name="">
		<property name="bFullscreen" value="false"/>
		<property name="nScreenWidth" value="2560"/>
		<property name="nScreenHeight" value="1440"/>
		<property name="bMuteSoundEffects" value="true"/>
		<property name="bMuteMusic" value="true"/>
	</object>
</objects>