Revert custom player collision box and step height commits

These caused inability to pass through 2 node high spaces or step up onto slabs
or steps when a new client connected to an older server.

src/content_cao.h

@@ -154,12 +154,6 @@ public:
 
 	scene::IBillboardSceneNode *getSpriteSceneNode();
 
-
-	inline f32 getStepheight() const
-	{
-		return m_prop.stepheight;
-	}
-
 	inline bool isPlayer() const
 	{
 		return m_is_player;