Reverting 'OperationsHolder' static field solution because it doesn't work with TaskService class inheritance (revert of c01b8f78)

JBPM-3589 BZ 854612: Adding an index to the EventTypes table: via .hbm.xml (cleaned up unnecessary hib4 profile in pom.xml as well)

JBPM-3773 - NotSerializableException: org.jbpm.bpmn2.xml.ProcessHandler$1 when trying to serialize CancelActivity action

Added 'for' to line 867.

JBPM-3772, BZ 854704: moving assembly files (etc.) to specific war modules to fix problems with distribution naming. (cherry pick d3c545b2)

- task statistics service initial impl

BZ 854704 Remove signature files before repackaging gwt-console-server war.  (cherry picked from commit a119d30d)

(cherry picked from commit 1d5af3a6)

(cherry picked from commit 62bfeb5e)

JBPM-3772: dependency fixes and other clean-up in jbpm-gwt, human-task, persistence and workitems (cherry picked from commit f526becc)