LOGBACK-929: daemonized threads created by logback executor service.

LOGBACK-929: fix spacing per Tony's request.

fixed typo in the paragraph relating to ExecutionServiceUtil changes (PR #187)

Fix for LOGBACK-894 cleanByPeriodOffset add time check

- Properly close <p> tags in order to be XML well-formed
- minor edits in the paragraph relating to ExecutionServiceUtil changes
  (PR #187)

Escape XML &,",' in XMLLayout (LOGBACK-728)

Fix LOGBACK-728 and LOGBACK-440.

Add unit test for XMLLayout: validate against log4j.dtd found in log4j
(added as a test dependency).

As log4j-over-slf4j is a test dependency as well we must take care to
have log4j-over-slf4j first in the classpath so that it can take
precedence over log4j.

fixed flaky mocking in AbstractSocketAppenderTest due to multi-threading issues

Use response encoding when creating the printwriter or you will run into...

 LOGBACK-1008 ConfigurationDelegate.groovy should check AppenderAttachabable.

Add support for depth range to CallerDataConverter

Add request method to MDCInsertingServletFilter

Make sure TeeHttpServletResponse uses the response character encoding
when contructing a new writer.

Fixed typo in append-toMySQL-with-datasource.xml

LOGBACK-116: RollingCalendarTest fails when user.timezone is not CEST

simplification of SocketApender connection logic

LOGBACK-909 Fix race condition in SMTPAppenderBase

The caller converter of the pattern layout supports specification
of depth which changes the number of levels it writes out
from the stack trace. If you need to skip some levels and write out
a range of stack trace elemens you cannot do so. This commit adds
support for ranges using the double dot ("..") notation. It can be useful
while using for example Scala traits to simplify logging which causes
the file and line number to be incorrect. This way the user can see
the actual place where logging was called.