Some connection pool specific keys were still advertized in the
documentation.

Closes gh-5143

Previously, both Atomikos and Bitronix were bound on the `spring.jta`
namespace which makes very hard to figure out which property belong to
which implementation. Besides, `AtomikosProperties` only exposed public
setter which does not generate any useful meta-data.

This commit moves the external configuration for Atomikos and Bitronix to
`spring.jta.atomikos.properties` and `spring.jta.bitronix.properties`
respectively. It also improves the meta-data support for those two
namespaces.

Closes gh-5165

Spring Data Couchbase 2.0 sets the default consistency to "update-after"
which is good for performance reason but can be quite confusing. Since
the team has decided to switch to "read-your-own-writes" in 2.1, Spring
Boot already offers the improved default right now.

This commit exposes an additional property that can be used to change
the Couchbase's default consistency.

Closes gh-5159

See gh-3498

Closes gh-5160

Expose an `auto-index` property that controls if views and indexes
should be created automatically.

Update the sample so that it uses this new property, lowering the manual
steps to make it working on a vanilla couchbase server.

See gh-3498

Closes gh-5155

* pr/3499:
  Polish contribution
  Add Couchbase support

Closes gh-3499

Closes gh-3498

Closes gh-5151

Uses interfaces instead of DTOs to implement projections. Works
around DATAJPA-864 [0].

[0] https://jira.spring.io/browse/DATAJPA-864

Closes gh-5120

See gh-5141

See gh-4097 and changes in 2522a5f9

Previously, if one wants to create a custom `JmsListenerContainerFactory`
or `RabbitListenerContainerFactory`, a bunch of code from the auto-
configuration must be duplicated.

This commit introduces two services to configure such factory for JMS
and AMQP with the same sensible defaults that were applied by the
auto-configufrations.

Closes gh-5138

Previously, when DevTools was restarting the application it would
use reflection to run all of the JVM's shutdown hooks. This was done
to close any SpringApplications' application contexts. Unfortunately,
it had the unwanted side-effect of running other shutdown hooks as
well.

The other shutdown hooks were often written with the, entirely
reasonable, expectation that they would only be called when the JVM
was shutting down. Calling them at another time could leave the
hook's library in an unexpected state. One such example is Log4J2
which was worked around in aaae4aa3 (see gh-4279). Another is the
problem with Eureka (see gh-4097). There's no work around for this
problem, even with reflective hackery, hence the change being made
here.

This commit updates the Restarter so that shutdown hooks are no longer
called during a restart. This removes the chance of a restart having
the unwanted side-effect of leaving a third-party library in a broken
state. RestartApplicationListener now prepares the Restarter with the
root application context, and the Restarter then closes it as part of
the restart. The changes have been tested with an application that
uses a single context and an application with a context hierarchy.

Closes gh-4097

Previously, if an application had been started without remote
debugging enabled, an attempt to connect to it via
RemoteSpringApplication and the HTTP tunnel would result in the
application being hammered by connection attempts for 30 seconds.

This commit updates the tunnel server to respond with Service
Unavailable (503) when a connection attempt is made and the JVM
does not have remote debugging enabled. When the client receives a
503 response, it now logs a warning message describing the possible
problem before closing the connection.

The client has also been updated to provide improved diagnostics when
a connection to the tunnel server cannot be established, for example
because the remote URL is incorrect, or the remote application isn't
running.

Lastly, the client has been updated so that it continues to accept
connections when a connection to the server is closed. This allows
the user to correct a problem with the remote application, such as
restarting it with remote debugging enabled, without having to also
restart the process that's running RemoteSpringApplication.

Closes gh-5021

Previously, WebRequestTraceFilter would call request.getParameterMap()
before deciding whether or not the parameters should be included in
the trace. For a POST request, this had the unwanted side-effect
of always reading the request body.

This commit updates WebRequestTraceFilter so that it checks that
parameters are to be included in the trace before calling
request.getParameterMap()

Closes gh-5089

Closes gh-5122

Closes gh-5073

Closes gh-5131