Support meta-annotation attr overrides in the TCF

Prior to this commit, the Spring TestContext Framework (TCF) supported
the use of test-related annotations as meta-annotations for composing
custom test stereotype annotations; however, attributes in custom
stereotypes could not be used to override meta-annotation attributes.

This commit addresses this by allowing attributes from the following
annotations (when used as meta-annotations) to be overridden in custom
stereotypes.

- @ContextConfiguration
- @ActiveProfiles
- @DirtiesContext
- @TransactionConfiguration
- @Timed
- @TestExecutionListeners

This support depends on functionality provided by
AnnotatedElementUtils. See the 'Notes' below for further details and
ramifications.

Notes:

- AnnotatedElementUtils does not support overrides for the 'value'
  attribute of an annotation. It is therefore not possible or not
  feasible to support meta-annotation attribute overrides for some
  test-related annotations.
- @ContextHierarchy, @WebAppConfiguration, @Rollback, @Repeat, and
  @ProfileValueSourceConfiguration define single 'value' attributes
  which cannot be overridden via Spring's meta-annotation attribute
  support.
- Although @IfProfileValue has 'values' and 'name' attributes, the
  typical usage scenario involves the 'value' attribute which is not
  supported for meta-annotation attribute overrides. Furthermore,
  'name' and 'values' are so generic that it is deemed unfeasible to
  provide meta-annotation attribute override support for these.
- @BeforeTransaction and @AfterTransaction do not define any attributes
  that can be overridden.
- Support for meta-annotation attribute overrides for @Transactional is
  provided indirectly via SpringTransactionAnnotationParser.

Implementation Details:

- MetaAnnotationUtils.AnnotationDescriptor now provides access to the
  AnnotationAttributes for the described annotation.
- MetaAnnotationUtils.AnnotationDescriptor now provides access to the
  root declaring class as well as the declaring class.
- ContextLoaderUtils now retrieves AnnotationAttributes from
  AnnotationDescriptor to look up annotation attributes for
  @ContextConfiguration and @ActiveProfiles.
- ContextConfigurationAttributes now provides a constructor to have its
  attributes sourced from an instance of AnnotationAttributes.
- ContextLoaderUtils.resolveContextHierarchyAttributes() now throws an
  IllegalStateException if no class in the class hierarchy declares
  @ContextHierarchy.
- TransactionalTestExecutionListener now uses AnnotatedElementUtils to
  look up annotation attributes for @TransactionConfiguration.
- Implemented missing unit tests for @Rollback resolution in
  TransactionalTestExecutionListener.
- SpringJUnit4ClassRunner now uses AnnotatedElementUtils to look up
  annotation attributes for @Timed.
- TestContextManager now retrieves AnnotationAttributes from
  AnnotationDescriptor to look up annotation attributes for
  @TestExecutionListeners.
- DirtiesContextTestExecutionListener now uses AnnotatedElementUtils to
  look up annotation attributes for @DirtiesContext.

Issue: SPR-11038
Merge pull request #421 from sbrannen/SPR-11038

* SPR-11038:
  Support meta-annotation attr overrides in the TCF