FontConstructor: Hide the exposed strings and add them in class API d…

…oc to minimize footprint. Review of Harvey.

Since accessing the static final exposed strings would trigger static initialization,
setting the properties this way would not work anyways (if not inlined ..).
Well.

src/jogl/classes/com/jogamp/graph/font/FontFactory.java

@@ -38,9 +38,17 @@
 import jogamp.graph.font.JavaFontLoader;
 import jogamp.graph.font.UbuntuFontLoader;
 
+/**
+ * The optional property <i>jogamp.graph.font.ctor</i>
+ * allows user to specify the {@link FontConstructor} implementation.
+ * <p>
+ * Default {@link FontConstructor} is {@link jogamp.graph.font.typecast.TypecastFontConstructor},
+ * i.e. using our internal <i>typecast</i> branch.
+ * </p>
+ */
 public class FontFactory {
-    public static final String FontConstructorPropKey = "jogamp.graph.font.ctor";
-    public static final String DefaultFontConstructor = "jogamp.graph.font.typecast.TypecastFontConstructor";
+    private static final String FontConstructorPropKey = "jogamp.graph.font.ctor";
+    private static final String DefaultFontConstructor = "jogamp.graph.font.typecast.TypecastFontConstructor";
 
     /** Ubuntu is the default font family */
     public static final int UBUNTU = 0;