JBPM-4314,DROOLS-192 Remove 4.x legacy API
Removing unused dom4j dependencies because they can cause classloading problems.
JBPM-4320: Persistent meta-data in BPMN2 process
 - adding some additional commands
 - add missing task audit class in persistence.xml
 - update to dashboard url in installer
 - adding task audit classes in installer persistence.xml
Fixed grammar on feedback related to human task status exception
messages.
- fixing support for stop/fail/exit audit task
removed duplicate references in persistence.xml to

    <class>org.jbpm.services.task.impl.model.CommentImpl</class>
    <class>org.jbpm.services.task.impl.model.DeadlineImpl</class>
- updating taskaudit entities to auto increment id
JBPM-4322 - GetProcessInstanceIdByCorrelation fails with hibernate 4.3
BZ-1090467 - 'Deployment of unit failed: Cannot find ksession with name' doesn't help to identify the problem
JBPM-4326 - TaskRule service does not allow to reason over task variables
BZ-1082717 - Add remote API operations to get process definitions in a deployment unit
BPMSPL-37-attachment-support: added jbpm-document module to allow attach documents to tasks
Revert "BPMSPL-37-attachment-support: added jbpm-document module to allow attach documents to tasks"

This reverts commit 97475b2237a4e055cf48c9e9007838bfebf6f61f.
 - setting some jbpm-workitem dependencies as optional
JBPM-4328 - Unify asynchronous operations execution to utilize jbpm executor (JBPM-4329,4330)
JBPM-4328 - Unify asynchronous operations execution to utilize jbpm executor (JBPM-4329,4330) - javadocs dependency added