Fix the exception occuring because LoggingEvent is not serializable by using LoggingEventVO instances for the benchmark.

This went unnoticed because HSQLDB and H2 dialects are identical as of now.

The logback-access module now targets Tomcat 7.x and Jetty 7.x & 8.x as its servlet container platforms.

- updates logback-access and jetty 7 support

AppenderAttachableImpl now uses CopyOnWriteArrayList
instead of ReadWriteLock.

- Given output prdoduced by LBCORE224Test.javam, the Reduce.java
  applicaiton can remove matching LOCK/UNLOCK lines making it much
  easier to interpret the output

- refactoring of Jetty related test cases

as subjoinX
- intendation changes

LBCLASSIC-275 - LoggingEvent casts to LogbackMDCAdapter without checking