Fixed timing issue in JettyBasicTest

Optimization: use Collections.emptyMap() in LoggingEvent

fixes viewAsGroovy Link for configurations with styling

* modifies ignore-regex in order to ignore <span> tags correctly

The following unit tests were failing because they were expecting the
logger context to have package data enabled by default, but the default
had been changed to false in 8141f88e.

 * ExtendedThrowableProxyConverterTest.integration
 * RootCauseFirstThrowableProxyConverterTest.integration

This patch explicitly enables packaging data for the test's logger context.

Add japanese translation for logback manuals.

Add XML support to en/disable stacktrace package detail

This prevents developers from attempting to modify event's mdc map. For example by invoking

event.getMDCPropertyMap().put("k", "v");

This fixes LOGBACK-1063 by ricochet.

with the latest version the release process fails

Changed the default enable status of packaging info in stacktraces
to be disabled to avoid the expensive lookup unless requested.

Added an XML attribute "packageTrace" to <configuration> in order to
allow enabling or disabling the packaging info in stacktraces. When
the attribute is omitted, the default setting is assumed (disabled).

To enable package detail in logback.xml:

  <configuration packageTrace="true">
    ...
  </configuration>

LOGBACK-730
LOGBACK-966

LOGBACK-1046 fix suggestion

Documentation: Fix <h3> tag issue

[LOGBACK-540] Filtering out selected stack trace frames

Plugin and dependency updates plus add missing overrides in logback-access