some steps of act-1560
act-1560
update userguide for delete taskListerEvent
sample implementation of ACT-1738
Upgrade to commons-lang3. See http://commons.apache.org/proper/commons-lang/
try to add test case for MDC. Not working yet
complete implementation of ACT-1738
Merge remote-tracking branch 'upstream/master' into act-1738
add files for act-1738
add files for act-1738
add comments
update userguide
enhance MDC documentation
correct typo
repackage LogMDC
Merge branch 'master' of https://github.com/marcusk24/Activiti into CmdTC

Conflicts:
	modules/activiti-spring/src/main/java/org/activiti/spring/components/scope/ProcessScope.java
- add MySQL QA configuration.
- misc minor fixes.
Merge branch 'master' of https://github.com/marcusk24/Activiti into CmdTC
root pom.xml: downgrade maven-jar-plugin to 2.3.2 because of manifest bug in m2e.
[ACT-1758] Add ability to flexibly configure the command interceptor chain by moving their configuration from the interceptors themselves to CommandConfig. Simplified the command-executor related functionality in implementations of ProcessEngineConfiguration. CommandExecutor split into seperate CommandExecutor and CommandInterceptor interfaces. CommandExecutor now has 2 execute methods, 1 with and 1 without the CommandConfig. CommandInterceptor only has the one with CommandConfig. CommandExecutorImpl renamed to CommandInvoker.