SDOAware interface has been removed.
 ILoggerEvent interface no longer extends SDOAware.
 
 Appenders which rely on serialization invoke the appropriate PreSerializationTransformer
 to obtain a serializable representation of the event they are processing. 

This fairly extensive commit in terms of the number of affected
classes but relatively small conceptually. It is a refactoring of the
LoggingEvent class. The LoggingEvent class now implements the
ILoggingEvent interface which essentially contains getter methods with
no setters.  LoggingEvent is no longer serializable because the
relavant serialization code has been moved into LoggingEventSDO. A
LoggingEvent object now requires transformation into LoggingEventSDO
object before serializaiton. LoggingEventSDO class implements the
ILoggingEvent interface. SDO stands for Serialable Data Object.

All logback-classic components, including appenders, layouts,
converters now operate on ILoggingEvent instances. In other words,
logback-classic module is now a specialized processing chain for
ILoggingEvent objects, instead of LoggerEvent objects previously.

The getStartTime method which was previously part of LoggingEvent has
migrated to the Context interface. This change is a nice fit from a
conceptual point of view.

All tests pass. Performance is has not been degraded. 

In the future commits, the LoggerRemoteView may be renamed as
LoggerSDO, and similarly, LoggerContextRemoteView as LoggerContextSDO.

- to method to remove files is called "unlink" in perl

Also added an FAQ entry about logback dependencies

This fixes LBGENERAL-8

  logback-access uses it as well.
  
- Added unit tests in relation with default component class mapping rules in Joran. 
  See also jira issue LBCLASSIC-103

Related to LBCORE-83.
 

- Added StatusMessage viewer servlet for lb-classic called ViewStatusMessagesServlet. 

- Added StatusMessage viewer servlet for lb-access called ViewStatusMessagesServlet. 
  It works with Tomcat but not Jetty.

- Added relevant documentation.

- Fix LBCORE-74
  
  HTMLLayoutBase now takes into custom conversion words.
  
- Moved StringListAppender to c.q.l.classic.testUtil package

- cleaned up config files so that "level" is an XML attribute and not
  an XML element

- updated Gmail related examples

- LBCLASSIC-100

  Evaluators are now wired into an appender automatically (implicit
  rules) without the help of EvaluatorAction. EvaluatorAction is now
  only needed for global evaluator elements.

  It follows that name attribute is necessary only for global
  evaluators. Embedded evaluators no longer need a name.

  EvaluatorAction has been modified to accept evaluators of any type
  and not just JaninoEvaluators.

- add tests for verifying that parameter types which are concrete classes 
  can be instantiated by implicit actions
- ongoing work on evaluators

  Thus, it is no longer necessary to specify the class name as an xml attribute for sub-components
  
- refactoring of sibling appender 

- logback-access tests are now all JUnit4

 - Absorb thrown SecurityException/AccessControlException when accessing system properties
   This fixes LBCLASSIC-86

run on older JDKs we make JDK 1.6 a requirement for running the DBAppenderIntegration tests. 

We now use sqljdbc4. (note the suffix 4)

  between successive runs