See gh-3569

Fixes gh-3527

Closes gh-3569

This commit provides a single endpoint, /actuator, that serves HTML
(the HAL browser) or JSON depending on the request’s accept header
that enables discovery of all of the actuator’s other endpoints.

When the management context path is configured, the /actuator endpoint
moves to the configured path, e.g. if the management context path is
set to /management, the actuator endpoint will be available from
/management.

Closes gh-3696

See gh-3539

See gh-3557

Closes gh-3715

Closes gh-3700

Improve the documentation on using two entity managers if Spring Data is
used.

Closes gh-3433

Make it more clear that the `ErrorPage` path requires an URL mapping to
be registered.

Closes gh-3698

See gh-3684

Closes gh-3643

Closes gh-3652

Closes gh-2671

This commit adds a new property, logging.exception-conversion-word,
that can be used to configure the conversion word that is used when
logging exceptions. The default value, %rEx, will log exceptions
with the root cause first and include class packaging information in
the stack trace. The new property is supported when using either
Logback or Log4J2.

Closes gh-3684

Upgrade documentation for the `hal` and `links` endpoints as they are
not using the root anymore.

Closes gh-3621

Update LinksMvcEndpoint and HalBrowserMvcEndpoint so that no longer try
to use the `/` context path. Links are now available from `/links` and
the HAL browser is available from `/hal`.

The actuator HAL browser now works with either WebJars or the Spring
Data version. It also now transforms the initial HTML so that the
form is pre-populated with `/links`.

When using Spring Data's HAL browser, the root includes a link to
`/links` with a rel of `actuator`.

See gh-3621

Replace `Link :` prefixes in the restdoc headings with link icons next
to the HTTP request. This fixes render issues with the titles and allows
the TOC to still function correctly.

Fixes gh-3689

Update `spring-boot-actuator-docs` to generate rest documentation in
the compile phase.

Add a new `@ImportAutoConfiguration` annotation that can be used by
tests that wish to selectively import certain auto-configuration
classes. Also add `@AutoConfigurationPackage` so that package
registration is decoupled from `@EnableAutoConfiguration`.

An added benefit of the change is @EnableAutoConfigurationImportSelector
can now be subclassed to provide custom annotation support if needed.

Fixes gh-3660
See gh-2772

Revert commit 1d31d23e to
remove `include` from `@EnableAutoConfiguration`. We'll
add a dedicated annotation instead to fix this.

See gh-3660

This reverts commit f7619706.

See gh-3569

This commit updates the default logging configuration for both Logback
and Log4J 2 to include class packaging information when logging
exceptions and to log the root cause first.

Closes gh-3398
Closes gh-3399

Closes gh-3569

Closes gh-3675

Closes gh-3676

Closes gh-3677

Closes gh-3678

Closes gh-3679

Closes gh-3680

Closes gh-3682

Closes gh-3683