LOGBACK-898 never blocking async appender

Allows the AsyncAppender to be configured to be never block on
a full queue.

This is taken from Jeff Wartes original patch:

http://jira.qos.ch/browse/LOGBACK-898

Bumping to next development version

Fixed a bug in TimeBasedFileNamingAndTriggeringPolicyBase

Optimization in LogbackMDCAdapter.get(String)

The configuration refers to these as  suite names,  not spec names.

Formatted LogbackValve with code style settings

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.