isCP437 for fonts

com/danitheskunk/skunkworks/gfx/font/FontTTF.java

@@ -81,6 +81,11 @@ public class FontTTF implements IFont {
 		return chars.get(ch).advance;
 	}
 
+	@Override
+	public boolean isCP437() {
+		return false;
+	}
+
 	@Override
 	public int getLineHeight(int ch) {
 		cacheChar(ch);

com/danitheskunk/skunkworks/gfx/font/FontTileset.java

@@ -19,6 +19,11 @@ public class FontTileset implements IFont {
 		return charSize.getX();
 	}
 
+	@Override
+	public boolean isCP437() {
+		return true;
+	}
+
 	@Override
 	public int getLineHeight(int ch) {
 		return charSize.getY();

com/danitheskunk/skunkworks/gfx/font/IFont.java

@@ -8,4 +8,5 @@ public interface IFont {
 	Vec2i getOffset(int ch);
 	ITexture getTexture(int ch);
 	int getXAdvance(int ch);
+	boolean isCP437();
 }