INT-3160: IRMHM: Use Protected Method from Super

JIRA: https://jira.springsource.org/browse/INT-3160

Prior to SPR 4.0 `RequestMappingHandlerMapping#createRequestMappingInfo` was `private`.
So, there was reason to to use reflection in the `IntegrationRequestMappingHandlerMapping`
INT-3156: Resolve deprecations according to SPR 4

JIRA: https://jira.springsource.org/browse/INT-3156

* Resolve `@SuppressWarnings("deprecation")` for HTTP, JDBC modules
* Remove `ParameterizedTypeReference`
* Add `@SuppressWarnings("deprecation")` to `HttpRequestHandlingEndpointSupport`
for `MappingJacksonHttpMessageConverter`
INT-3165: Deprecate Jackson 1.x Usage

JIRA: https://jira.springsource.org/browse/INT-3165

INT-3165 Polishing

Remove unnecessary SuppressWarnings.
INT-3184: Test HTTP Matrix Variables

JIRA: https://jira.springsource.org/browse/INT-3184

* Change `IntegrationRequestMappingHandlerMapping` to postpone
Handlers detection as late as possible using `ApplicationListener<ContextRefreshedEvent>`
Revert "INT-3184: Test HTTP Matrix Variables"

This reverts commit b607b6d3c92c511baa857bfbf8d4a916085f35af.
INT-3184: Test HTTP Matrix Variables

JIRA: https://jira.springsource.org/browse/INT-3184

* Change `IntegrationRequestMappingHandlerMapping` to postpone
Handlers detection as late as possible using `ApplicationListener<ContextRefreshedEvent>`.
This is needed, because `RequestMappingInfoHandlerMapping#afterPropertiesSet()`
iterates over beans from `BeanFactory` to detect MVC Handlers. But at the same time
Integration Endpoints require `requestChannel` as dependency and those may be postponed
for `auto-creation` by `ChannelInitializer` - late-binding issue.
INT-3052 RestTemplate with TypeReference for HTTP

JIRA: https://jira.springsource.org/browse/INT-3052

Add support of `ParameterizedTypeReference` as a result of
`expectedResponseTypeExpression` evaluation for
`RestTemplate.exchange` with `ParameterizedTypeReference` parameter

Now `expectedResponseTypeExpression` can be evaluated to `Class<?>`,
`String` and `ParameterizedTypeReference<?>`
INT-3242 Final Polish for 4.0.0.M2

- Rename EiMessageHeaderAccessor to IntegrationMessageHeaderAccessor
- Remove GenericMessage
- Minor TODOs
- Start a new What's new" chapter in the reference

JIRA: https://jira.springsource.org/browse/INT-3242