Don't flush in ErrorPageFilter for < 400 response that's committed

Previously, for a non-async response with a successful status (< 400),
ErrorPageFilter would always call flushBuffer. This triggers an
exception in Tomcat if the client has closed the connection before the
response has been fully sent. In this case, Tomcat treats the response
as successful and commits it before control returns to the filter.

This commit updates ErrorPageFilter to only perform the flush if the
response has not already been committed, leaving any further flushing
that may be necessary to be handled by the servlet container.

Fixes gh-1938
Merge branch '1.1.x'
Omit null pathInfo from ErrorPageFilter's error message

Fixes gh-1944
Merge branch '1.1.x'
Upgrade to Spring Integration 4.0.5.RELEASE

Closes gh-1905
Upgrade to Spring AMQP 1.3.7.RELEASE

Closes gh-1906
Upgrade to Tomcat 7.0.57

Closes gh-1936
Merge branch '1.1.x'

Conflicts:
	spring-boot-dependencies/pom.xml
Use HttpMapper properties only if defined

See gh-1923
Test that HttpMapper properties are only used when they’re defined

Closes gh-1923
Merge branch 'jackson-mapper'
Update JackonAutoConfiguration to apply all http.mappers properties

Previously, only the http.mappers.json-sort-keys property was applied
by JacksonAutoConfiguration. This commit updates it to also apply the
http.mappers.json-pretty-print property as well.

See #1919
Test that http.mappers props are applied by JacksonAutoConfiguration

Closes gh-1919
Merge branch 'gh-1919' into 1.1.x
Merge branch '1.1.x'
Deprecate http.mappers.* properties

The http.mappers.* configuration properties assumed that the mapping
was JSON (on of the property names was jsonPrettyPrint) and also only
exposed a small subset of the configuration options supported by
Jackson (and GSON). The property names implied that it would configure
all HTTP mapping, however it was ignored by GsonAutoConfiguration.

This commit deprecates the support for http.mappers.* in favour of
configuring Jackson or Gson instead. Jackson can be configured
declaratively using the spring.jackson.* properties or programtically.
Gson can be configured programatically by using a GsonBuilder to
create a Gson instance with the desired configuration.
gh-1946 has been opened to add support for declarative configuration
of Gson.

Closes gh-1945
Apply spring.jackson.* config to HypermediaAutoConfiguration’s ObjectMapper

Previously, HypermediaAutoConfiguration would trigger the creation of
an ObjectMapper bean named _halObjectMapper. This bean did not have the
spring.jackson.* configuration applied to it, however its presence
would revent JacksonAutoConfiguration from creating its
ObjectMapper. This left the user with an ObjectMapper that did not
honour the spring.jackson.* configuration.

This commit updates HypermediaAutoConfiguration to use the
Jackson2ObjectMapperBuilder that may have been created by
JacksonAutoConfiguration. If the builder exists it is used to configure
the _halObjectMapper bean.

Fixes gh-1949
Improve relaxed enum binding

Update RelaxedConversionService to support more relaxed enum binding.

Fixes gh-1950
Add profile to ConfigFileApplicationListener log

Fixes gh-1948
Merge branch '1.1.x'