Improve State Javadoc

Author: iluwatar

state/src/main/java/com/iluwatar/state/App.java

@@ -2,10 +2,14 @@
 
 /**
  * 
- * In State pattern the container object ({@link Mammoth}) has an internal state object ({@link State}) that
+ * In State pattern the container object has an internal state object that
  * defines the current behavior. The state object can be changed to alter the
  * behavior.
  * <p>
+ * This can be a cleaner way for an object to change its behavior at runtime 
+ * without resorting to large monolithic conditional statements and thus improves 
+ * maintainability.
+ * <p>
  * In this example the {@link Mammoth} changes its behavior as time passes by.
  * 
  */