Added support for setting creature direction (limited to NPC's).

Support setting of NPC directions. Like so:

![direction-1](https://cloud.githubusercontent.com/assets/1935706/5331590/a32fbcf2-7e96-11e4-8629-352e37394c64.png)
![direction-2](https://cloud.githubusercontent.com/assets/1935706/5331223/9e68948a-7e84-11e4-9062-9d203330ad4a.png)

This will save in the spawn xml like so:
```
<spawn centerx="32962" centery="32076" centerz="7" radius="1">
	<npc name="Alvar the Warchief" x="0" y="0" z="7" spawntime="60" direction="3" />
</spawn>
```
If there is no direction tag specified it will keep the NPC's facing SOUTH (2).