INT-2982 Fix Hard-Coded Ports in Syslog Tests

Use the port finder to find an available port; using
hard-coded ports can cause issues with concurrent builds.

One test found a port in the XML but was still hard-coded
in the test itself rather than retrieving the port from
the adapter.

Also, stop the adapters when tests complete.
Merge pull request #790 from garyrussell/INT-2982a

* garyrussell-INT-2982a:
  INT-2982 Fix Hard-Coded Ports in Syslog Tests
INT-2620 Fix Race Condition in Failover Tests

Sporadic test failures (fairly consistently on Mac).

Problem was some tests sent a message to a client socket before the
close notification had been received.

Wait for client connection to close rather than waiting for the
server to stop.

Also, with NIO, close the channel on accept exception.

Also improve debugging by including a log of new connections
including the id.
Merge pull request #793 from garyrussell/INT-2620

* garyrussell-INT-2620:
  INT-2620 Fix Race Condition in Failover Tests
INT-2991 Filtered Messages Marked SEEN

Missing else clause caused filtered email messages to
still be marked as SEEN. Also marked un-filtered messages
twice if a filter was present.

Add else; add tests.
Merge pull request #784 from garyrussell/INT-2991

* garyrussell-INT-2991:
  INT-2991 Filtered Messages Marked SEEN
INT-2312: HTTP RequestMapping support

The general idea to use Spring-MVC as much as possible.

* introduce `RequestMapping`, `IntegrationRequestMappingHandlerMapping`
* introduce XSD nested element `<request-mapping>` for HTTP Inbound Endpoints
* introduce `inboundCommonAttributes` XSD attributeGroup for HTTP Inbound Endpoints
* introduce `IntegrationNamespaceUtils#createExpressionDefIfAttributeDefined` & `IntegrationNamespaceUtils#createDirectChannel`
* remove deprecated `name` attribute
* remove `UriPathHandlerMapping` as superseded by `IntegrationRequestMappingHandlerMapping`

JIRA: https://jira.springsource.org/browse/INT-2312, https://jira.springsource.org/browse/INT-2619
INT-2528: Remove deprecations in HTTP module

JIRA: https://jira.springsource.org/browse/INT-2528
INT-2312: Doc for `<request-mapping>`

* Add description to Reference Manual about `<request-mapping>`
* Additional doc polishing
* Add additional test for `<request-mapping>`
* Polishing according PR's comments
INT-2312: 'What's new' and http doc polishing
INT-2312: Polishing 'What's new' after rebase
INT-2312: Add Jackson 2 support for HTTP-inbound
INT-2312: Rebase polishing
INT-2312: Review & email discussion polishing

* Make `RequestMapping` public
* Introduce `HttpContextUtils` and move `HANDLER_MAPPING_BEAN_NAME` to it
* Revert and deprecate public API
* Improve JavaDocs
* Improve Reference Manual
* Rework `IntegrationRequestMappingHandlerMapping` according to email discussion