Proposal for having distinct Java package names in different modules

Hello,

As explained in http://forums.activiti.org/content/exposing-activiti-engine-through-rest-osgi-container-virgo and http://jira.codehaus.org/browse/ACT-1786 , I believe there would be some benefit if each Activiti module could have its own base package name, and avoiding classes of the same package be found in more than one module.

The proposed pull request (my very first one! :-) ) is a proposal to fix the current situation.
It is composed of:
* import and package statements updated according to the base package names as found on the JIRA issue
* move of Java and test bpmn20.xml files in correct folders
* updated reference of files/resources inside unit tests
* updated FQN of classes referenced in several web.xml files
* updated FQN of some classes in chapter 14 of the user guide

All the unit tests are green on my computer, and I have been able to deploy the applications on a local Tomcat 6 instance.

If you believe this is a valuable contribution, feel free to integrate it!

Thank you,



Dimitri