v0.7.4b: cleaned up some miscellaneous android dependencies

SPD-classes/src/main/java/com/watabou/noosa/RenderedText.java

@@ -26,6 +26,8 @@ import android.graphics.Canvas;
 import android.graphics.Paint;
 import android.graphics.Typeface;
 
+import com.badlogic.gdx.Gdx;
+import com.badlogic.gdx.backends.android.AndroidApplication;
 import com.badlogic.gdx.graphics.Pixmap;
 import com.watabou.gltextures.SmartTexture;
 import com.watabou.glwrap.Matrix;
@@ -240,7 +242,7 @@ public class RenderedText extends Image {
 
 	public static void setFont(String asset){
 		if (asset == null) font = null;
-		else font = Typeface.createFromAsset(Game.instance.getAssets(), asset);
+		else font = Typeface.createFromAsset(((AndroidApplication)Gdx.app).getAssets(), asset);
 		clearCache();
 	}
 

SPD-classes/src/main/java/com/watabou/noosa/Scene.java

@@ -21,6 +21,7 @@
 
 package com.watabou.noosa;
 
+import com.badlogic.gdx.Gdx;
 import com.watabou.input.KeyEvent;
 import com.watabou.utils.Signal;
 
@@ -72,7 +73,7 @@ public class Scene extends Group {
 	}
 	
 	protected void onBackPressed() {
-		Game.instance.finish();
+		Gdx.app.exit();
 	}
 	
 	protected void onMenuPressed() {