Infer AnnotationAttributes method return types

- Drop 'expectedType' parameter from #getClass and #getEnum methods and
   rely on compiler inference based on type of assigned variable, e.g.

     public @interface Example {
         Color color();
         Class<? extends UserType> userType();
         int order() default 0;
     }

     AnnotationAttributes example =
        AnnotationUtils.getAnnotationAttributes(Example.class, true, true);

     Color color = example.getEnum("color");
     Class<? extends UserType> userType = example.getClass("userType");

   or in cases where there is no variable assignment (and thus no
   inference possible), use explicit generic type, e.g.

     bean.setColor(example.<Color>getEnum("color"));

 - Rename #get{Int=>Number} and update return type from int to
   <N extends Number>, allowing invocations such as:

     int order = example.getNumber("order");

These changes reduce the overall number of methods exposed by
AnnotationAttributes, while at the same time providing comprehensive
access to all possible annotation attribute types -- that is, instead of
requiring explicit #getInt, #getFloat, #getDouble methods, the
single #getNumber method is capabable of handling them all, and without
any casting required. And the obvious additional benefit is more concise
invocation as no redundant 'expectedType' parameters are required.

org.springframework.transaction/src/main/java/org/springframework/transaction/annotation/ProxyTransactionManagementConfiguration.java

@@ -44,7 +44,7 @@ public class ProxyTransactionManagementConfiguration extends AbstractTransaction
 			new BeanFactoryTransactionAttributeSourceAdvisor();
 		advisor.setTransactionAttributeSource(transactionAttributeSource());
 		advisor.setAdvice(transactionInterceptor());
-		advisor.setOrder(this.enableTx.getInt("order"));
+		advisor.setOrder(this.enableTx.<Integer>getNumber("order"));
 		return advisor;
 	}