touchimageview: Removed redundant static qualifier.

Nested enum types are implicitly static

src/main/java/com/ortiz/touch/TouchImageView.java

@@ -63,7 +63,7 @@ public class TouchImageView extends AppCompatImageView {
     //
 	private Matrix matrix, prevMatrix;
 
-    private static enum State { NONE, DRAG, ZOOM, FLING, ANIMATE_ZOOM };
+    private enum State { NONE, DRAG, ZOOM, FLING, ANIMATE_ZOOM };
     private State state;
 
     private float minScale;