Removed spaces from top-level directory names.

Spaces tend to cause annoyances in a Unix-style shell environment.
This change fixes that.

02_Amazing/java/AmazingGame.java

@@ -0,0 +1,6 @@
+public class AmazingGame {
+    public static void main(String[] args) {
+        Amazing amazing = new Amazing();
+        amazing.play();
+    }
+}